Types of Christianity in History Who Were the First Christians?

1. Christianity Was Always Massively Varied

'Christianity' is not a single religion dating from 2,000 years age. A long series of varied different religions, flowing on from one another, have all called themselves "Christian". Rightly so. The beliefs and form have changed so much from time to time that it is best to consider Christianity a series of religions and the word "Christianity" to be an umbrella term for multiple faiths all of which have the same name but different beliefs. Some historical forms of Christianity have made more sense, and some have made less sense, than the Christian mythology that is common today. Modern archaeology has uncovered many of these early forms of Christianity, and no longer can we say that modern-day Christianity in its various forms represents early Christianity. It hardly does. Christianity now is quite varied, but in history the varieties were much more exotic.
Some say that the reason there has been, and continues to be, so many versions of Christianity is that Christian theology contains contradictions and doesn't entirely make sense₁. Different sects are different attempts at resolving problems with Christian theory. Christians themselves documented early disputes over what beliefs their movement should have. The Church Father Irenaeus (130-202CE) listed twenty forms of Christianity that he himself was aware of₂. The Christian academic Origen was instrumental in the founding of Christian literary theology. In his book Against Celsus (248CE) he writes at length against a 2nd-century attack on Christianity that described it as being comprised of disparate groups. Celsus said that Christians "were divided and split up into factions, each individual desiring to have his own party. [...] Thus separated through their numbers, they confute one another. [... They] are determined in different ways by the various sects". And Origen agreed that this was the case, that "from the beginning there were differences of opinion among believers regarding the meaning of the books held to be divine" and the reason was that because important issues always cause strong differences of opinion₃. The expert in ancient prime sources Prof. Bart Ehrman likewise states that one of most common causes of forgeries and fabrications was the urgent need that believers had to put across their point of view to convince others - and that, unfortunately, included the far-too-common practice of writing in other people's names₄.
As Christianity continued and debate raged about the actual meaning of its various stories, the sects proliferated. In 384CE Epiphanus counted no less than 80 different forms of Christianity₂.

“During the first three Christian centuries, the practices and beliefs found among people who called themselves Christian were so varied that that the differences between Roman Catholics, Primitive Baptists, and Seventh-Day Adventists pale by comparison. Most of these ancient forms of Christianity are unknown to people in the world today. In the second and third centuries there were, of course, Christians who believed in one God. But there were others who insisted that there were two. Some said there were thirty. Others claimed there were 365.”

"Lost Christianities" by Bart Ehrman (2003)₅

“The history of early Christianity also includes many difficult conflicts between the competing claims of a still fragile Church with considerable political backing and a host of local cults that somehow deviate from the doctrine. In the case of Christianity, the great difficulty at first was to decide exactly what the doctrine was.”

"Religion Explained" by Pascal Boyer (2001)₆

“The historian, in speaking of Christianity, has to be careful to recognize the very great changes that it has undergone, and the variety of forms that it may assume even at one epoch.”

"History of Western Philosophy" by Bertrand Russell (1946)₇

“In the first few centuries CE there really was no such thing as 'the Church', only competing factions, of which the Literalists were one.”

"The Jesus Mysteries" by Timothy Freke & Peter Gandy (1999) [Book Review]₈

“[Christians] were divided and split up into factions, each individual desiring to have his own party. [...] Thus separated through their numbers, they confute one another. [... They] are determined in different ways by the various sects.”

Celsus (177CE)₉

These variant forms of Christianity did not spring from one source. They appeared from multiple points and multiple locations, overlapping with one another. It appears that Christianity was multifaceted at its very conception. The later writings that became the Bible, and the letters of St Paul, and the Orthodoxy of the later church, were created out of this mix, written as a result of the range of zany stories that Christianity had already embraced by the time it was growing. In other words, Christianity emerged gradually from previous folk stories. But what were the oldest and most ancient forms of Christianity like? And what happened to them? We will see!

2. Introductions to the Earliest Forms of Christianity

2.1. Mithraism and Christianity (200BCE +)

Many have realized that as Christianity copied, re-named and inherited many Pagan myths, such as those of Mithraism, that it is hard to pin down a "start" date for Christian ideas. If you go back far enough, Christian history is actually pagan history.

“Jesus, son of the Hebrew sky God, and Mithras, son of Ormuzd are both the same myth. The rituals of Christianity coincide with the earlier rituals of Mithraism, including the Eucharist and the Communion in great detail. The language used by Mithraism was the language used by Christians. [...] The idea of a sacrificed saviour is Mithraist, so is the symbolism of bulls, rams, sheep, the blood of a transformed saviour washing away sins and granting eternal life, the 7 sacraments, the banishing of an evil host from heaven, apocalyptic end of time when God/Ormuzd sends the wicked to hell and establishes peace. Roman Emperors, Mithraist then Christian, mixed the rituals and laws of both religions into one. Emperor Constantine established 25th of Dec, the birthdate of Mithras, to be the birthdate of Jesus too. The principal day of worship of the Jews, The Sabbath, was replaced by the Mithraistic Sun Day as the Christian holy day. The Catholic Church, based in Rome and founded on top of the most venerated Mithraist temple, wiped out all competing son-of-god religions within the Roman Empire, giving us modern literalist Christianity.”

"Mithraism and Early Christianity" by Vexen Crabtree (2002)

2.2. The Therapeutae (10CE)

Early Christians were criticized for copying Pagan ideas and stories and simply re-telling them. By the 4th century, the founders of the Christian Church sought evidence and historical proof to back up their mistaken opinion that Christianity was a new religion, derived from the new revelations of Jesus. Eusebius failed to find much evidence at all, except in the book of the first century author, Philo, who described a group of people who were clearly practicing Christian rituals:

“Eusebius, the fourth-century Church propagandist, could find little evidence from which to construct a history of Christianity, so he eagerly seized upon a description in one of Philo's books, of a group of Jews called the Therapeutae. Philo's description of their spring festival is reminiscent of the Christian celebration of Easter and Eusebius, therefore, claimed that he had discovered the earliest Christians in Alexandria. [... but] the spring, of course, was also the time when Pagans celebrated their festival of the dying and resurrecting godman, so Eusebius is unjustified in his assumption. Philo wrote about the Therapeutae in 10 CE, which would be 20 years before the supposed date of the crucifixion [...]. The Therapeutae are a group of Jews clearly practising a Jewish version of the Pagan Mysteries. [...] We can tell that the Therapeutae were Jews because they celebrated the Jewish festival of the Pentecost and kept sacred the Sabbath. [...]”

"The Jesus Mysteries" by Timothy Freke & Peter Gandy (1999) [Book Review]₁₀

Eusebius didn't know that Philo was writing 20 years too early, and he had therefore uncovered additional evidence that turn-of-the-millennium Jewish Paganism was almost identical to Christianity in terms of rituals and beliefs - if Jesus arrived and preached a New Testament, it seems he really didn't have anything new to say that wasn't already being practiced in a Christian way by pagans. The fact that "Philo can, in one sentence, compare the Therapeutae to both initiates of the Mysteries of Dionysis and the followers of Moses on the banks of the Red Sea shows just how integrated Pagan and Jewish traditions had become". They lived "near that great melting-pot of Pagan and Jewish cultures, Alexandria". "The Encyclopedia of Religion" by Eliade Mircea (1987) notes that their center was a hill above Lake Mareotis near Alexandria, and that they were similar to the Essenes₁₁.
Today when we trace the source of modern Christianity, we find that Christianity was codified in the 4th century. But in the fourth century, they didn't know what the source of Christianity was although critics said it was re-hashed paganism. So in the fourth century, they too searched in history to find the source of Christianity. They found the history of their religion to pre-date the actual founding of their own religion. The ancient history of Christianity is merged with the history of Paganism and the Church Fathers in the 4th century, so much closer to original Christianity than us, even mistook a group of pagans for early Christians. It wasn't the only time that they done this either, for when Bishop Melito in 160CE when in search of the ancient center of Christianity, he discovered only a group called the Ebionites, another ancient group that 4th century Christianity rejected as heretical.

2.3. The Dead Sea Scrolls (170BCE to 68BCE)

Jewish history led up to Christianity to the extent that Judaism and Christianity shared a blurred boundary in history. Jesus was a Jew and historians find it difficult to classify many early texts as either Jewish or Christian. This confusion is increasingly apparent in Greek-influenced Jewish texts, or, are they Jewish-influenced texts of Roman Mystery religions? Whatever they were, we know one thing: Christianity did not suddenly arrive as a bolt from the blue, but formed part of a progression in history that led from pure paganism, through to the more 'modern' Christianity of the 4th century, without any sudden spurt of change or innovation.
Stephen Hodge studied the Dead Sea Scrolls, which were written variously between 170BCE and 68BCE₁₂, and he usefully lists many of the similarities found in the Dead Sea Scrolls to the teachings and organisation of the Jewish Christianity which was to arise from the same period in time. He concludes that these Jewish documents make the teachings and appearance of Jewish Christianity less revolutionary.

“... the collection is really an invaluable cross-section of religious material that reveals for the first time just how rich and varied Jewish spiritual life was at that time. The scrolls offer an intellectual and devotional landscape into which Jesus and his movement can be placed. No longer does Jewish Christianity seem an inexplicable, isolated occurrence. [...]

In other words, the true value of the Dead Sea Scrolls is that they help provide a genuine context for what was to become Christianity. For example, they tell us just how widespread was the expectation and longing for a saving Messiah among Jews at that time, and that there were a number of competing theories about the expected role of this Messiah in the world of Judaism. The scrolls also reveal that the expectation found in the Gospels that the end of the world was imminent was a dominant belief in many quarters in Judaea.”

“All biblical scholars agree that, apart from their intrinsic value, the sectarian scrolls are of tremendous importance as background information to the social and religious conditions in Judaea that led to the rise of Christianity. [... There are] subtle implications that can be derived from the Qumran texts, for they not only provide interesting parallels to Christian concepts and practice but tend to reduce the uniqueness of the Yeshua movement. It is reasonable to assume that there was perhaps not that much direct contact between most members of each community, but that there was a pool of religious language and beliefs shared by many other Jewish groups which have long since disappeared.”

"Dead Sea Scrolls" by Stephen Hodge (2001) [Book Review]₁₃

Hodge lists many of the similar practices of the Dead Sea Scroll community and notes which ones were the same as those teachings accepted by the New Testament writers₁₄. The list includes:

1. Common ownership of property.
2. Exorcism: 'Allusions to this practice of exorcism are found in some of the writings from Qumran, such as the Genesis Apocryphon where it says, 'so I prayed for him ... and I laid my hands on his head; and the scourge departed from him and the evil spirit was expelled from him' (XX22.29)'.
3. Teachings on divorce and treatment of enemies: 'The scrolls have also been useful in providing valuable background information for ideas hitherto found only in the Gospels. For many years scholars had been baffled by the ban that Yeshua imposed upon divorce and remarriage, for this ruling had not been found in any other Jewish sources. but when works like the Temple Scroll and the Damascus Document came to light, it was soon noticed that members of the Community were similarly forbidden to divorce'
4. The ritual meal
5. The Beatitudes: 'Even teachings of Yeshua previously thought to be unique, such as the Beatitudes which he enumerates in the course of the Sermon on the Mount, find a parallel among the writings of the Qumran Community.' One such work is called The Beatitudes (4QBeat) where a number of virtues are mentioned in a very similar spirit to how they are in the New Testament. A series of beatitudes are listed which start 'Blessed be they who...'
6. Eschatological dualism - a great fight between good and evil during end times
7. Literary style and terminology: 'Writers in the Community used the unique pesher method of interpreting older scriptural texts in terms of contemporary events. When doing so, however, they expressed their interpretations in a heavily coded manner

2.4. Ebionite Christians (1st-4th Century)

Full page: "1st Century Christian Ebionites: The Original Christians?" by Vexen Crabtree (2012)

Ebionite Christians believed that all the Jewish Laws had to be obeyed; including the Sabbath and circumcision for all males. As such, they considered St Paul to be the archenemy of Christianity as he taught that people did not have to obey the Law in order to be saved. They believed Jesus was Human, and adopted by God as a perfect sacrifice.
The Ebionites were some of the original Christians: Jews who believed that Jesus was the Messiah. They populated the legendary Jerusalem Church. 'Ebionite' was sometimes used as a term to describe all Christians. Those who we now know of as Pauline Christians opposed the Ebionites, after discovering them and realizing that their beliefs differed. Authors such as Tertullian, Origen of Alexandria, and many other intolerant "heresy-hunters" wrote at great length against the Ebionites. Many of the claims made against them were based on misunderstandings of their beliefs, and many anti-Ebionite claims were plainly ridiculous. Pauline Christians eradicated the Ebionites, burning all of their books (none survived) and harassing and arresting the people until none were left. They edited Luke 2:33 and Luke 2:48 where Joseph was twice called the 'father' of Jesus so that it did not say so, and they also edited Luke 3:22 where it plainly stated, in accordance with Ebionite beliefs, that God adopted Jesus. Pauline Christians, as non-Jewish Romans, handily came across a mistranslated prophecy that said Jesus would be born of a virgin (like other Roman sons-of-gods), adding a whole two chapters to the beginning of Matthew to prove their point. These edits, when they were uncovered, have shown that the Ebionites were treated very cruelly and unfairly, and that the original readings of Matthew and Luke both support Ebionite Christianity, rather than the Pauline Christianity that the West has inherited.
If we were to guess which group was the more austere, holy and godly, we would have to guess it was the Ebionites rather than the Pauline Christians who slaughtered, slandered and oppressed them. Unfortunately the victors get to write history, and it is Pauline Christianity that became the legacy of the Roman Empire. After the fourth century, the Ebionites were vanquished.

2.5. Gnosticism (1st-7th Century)₁₅

Full page: "Gnosticism (1st-7th Century): The Birth of Christianity" by Vexen Crabtree (2013)

Gnosticism is an ancient religion stemming from the first century (approximately), and is an alternative messiah-religion that shares many features with Christianity. An inferior angelic being created the Earth, and this being is a hindrance to spiritual development. Many Gnostic schools taught that the Hebrew Scriptures were the religious creation of this inferior god. To trick this god out of power, a saviour was sent by the true god, and the sacrifice of this innocent man undermined the power of the old god, allowing the possibility for people to become saved and align themselves with the true god. Gnosticism was heavily attacked by the first Christian anti-heresy writers. Some authors such as Freke & Gandy (1999) argue that Christianity as we know it is a shallow version of Gnosticism which has mistaken symbolic stories for real ones₁₆, whereas many academics find that the historical and archaeological evidence is unclear: Christianity and gnosticism are related, but, and although we don't yet know which one came first, it seems that early Christianity was much more Gnostic than it is now, and perhaps the gnostic/literalist divide simply didn't exist for the first two centuries of Christian history. By the 7th century, literalist Christians had overwhelmed Gnosticism and related forms of Christianity, leaving us with modern Trinitarian Christianity.

2.6. Docetism (1st-7th Century)₁₇

Full page: "Docetism: Early Christianity of the 1st to 7th Century" by Vexen Crabtree (2012)

“Docetism and its various branches held that Christ's human body was merely a phantom, and that his suffering and death were but appearance. If he suffered, he was not God, they argued, if he was God, he did not suffer: a most reasonable conclusion.”

"Jesus Versus Christianity" by Alfred Reynolds (1993)₁₈

Some of the earliest groups of Christians were docetist but after the rise of Cappadocian and Pauline Christianity they were forcibly silenced and mostly eradicated. They believed that Jesus was a purely spiritual projection, sent by God to inform and lead. Joseph didn't impregnate Mary because Jesus didn't come from any physical seed; Mary conceived him to fulfil prophecy. Jesus couldn't have been physical because the physical world was fallen, imperfect and separate from god - in this docetist and gnostic Christians agreed. The reason Jesus didn't write anything himself or baptise anyone (John 4:1-2) is because he was a phantasm and could not. St Paul wrote that the Son came "in the likeness of flesh" (Romans 8:3).

2.7. Arian Christians (2nd-8th Century)

Full page: Arian Christianity (the Father is Greater than the Son): A Precursor to Modern Christianity

As Jewish Christianity began to develop its own character, Jesus was no longer considered to be just a man. He had a special relationship with god, and was perhaps conceived of by God before anything was created. But he was not an eternal man nor a god. Here is an excerpt from my page Arian Christianity (the Father is Greater than the Son): A Precursor to Modern Christianity:

What Was Christian Adoptionism?

Arianism describes the pre-trinitarian doctrine of a holy, but not a godly, Jesus. It is not always adoptionism and not always monotheistic, either. It was defined by a negative principal (that logically Jesus can't be God and still suffer on the cross). If Jesus was God (i.e., perfect), Arians realized, what chance would any Human have of imitating him? Although Arian-sounding theologies existed from the second century onwards, it only became a wide point of contention after the third century. In the third century Origen of Alexandria, the greatest theologian of his time, had declared that the Father was Greater than the Son₁₉. This principal was later named after its principal proponent and most articulate defender, Arius (256-336CE). It was opposed by Athanasius, who became a Nicene Christian from 325CE. Because of its popularity and its clear non-trinitarian view of Jesus, trinitarian Christians such as the Nicenes/Cappadocians have considered Arianism to be highly dangerous₂₀. In the Roman Empire, Arian Christianity was supplanted by intolerant Nicene Christianity by the 5th century, but remained the most popular form of Christianity amongst the tribes surrounding the empire, until the 8th century. [...]The eventual victory of the Cappadocian Nicene faith from 380CE meant that as the Empire collapsed, the Christianity that was left behind was the dark, violent, centralized type that did not tolerate dissent. By the late fourth century, a recognizable Roman Catholic Church had emerged. The doctrine of the Trinity had been created, and the vengeful violence of Nicene Christianity was in full, open, bloody view. Anti-semitism was given its official sanction. The edited Nicene Creed was the only form of belief that was to be tolerated. Inquisitors began reviewing religious beliefs, condemning victims to imprisonment, torture and public execution for failing to believe the right things. This state of affairs persisted and plunged Christian societies into a 1000-year long dark ages. If the Arians had survived the onslaught and been the religion that the Empire left behind, we would have been left with a Christianity that would have left a glowing legacy of Jesus. Instead, the Nicene's violence and intolerance won out, and the 'ages of faith' that resulted darkened humanity from the fifth until the fifteenth century.

2.8. Marcionite Christians (2nd-5th Century)

Full page: Christian Marcionites: 2nd Century Christianity

Marcionites believed that the God of the Old Testament (wrathful and angry) was a different God to the New Testament's mystical and forgiving one. Their reasoning was sensible and their knowledge of Christian texts of the time was the most involved. Their collection of Christian texts into a canon was the first ever collection and formed the template for what was to become the Bible.
At one point, the early Christian writings that were collected by Marcion, along with his own writings, were all destroyed. A domineering early Catholic Church, the Pauline Christians, committed themselves to a long-term campaign against these early Christians. Tertullian produced five volumes attacking Marcionism and distributed them throughout the Roman Empire. The honest intellectual and rational approach of Marcion to the Old Testament and the saving grace of Jesus were lost, burnt and oppressed by the more violent and aggressive Pauline Christians. It is ironic that in the name of 'good works', Pauline Christians murdered and tortured those who believed differently to themselves... if it is true, as Jesus says and as Marcion pointed out, that good trees do not produce rotten fruit, then have we ended up with a rotten tree grown from a rotten fruit, instead of the real Christianity as espoused by Jesus? If it is Christian duty to 'turn the other cheek', 'resist not evil', 'love your enemies' and 'love your neighbours as yourself', then it is clear that the Pauline Christians, who eliminated Marcionism and got to choose the books of the Bible, were not the true Christians.

2.9. Roman Christianity / Pauline Christianity (4th Century +)

Full page: St Paul - History, Biblical Epistles, Gnosticism and Mithraism and How Modern Christianity Began: The Cappadocian-Nicene-Pauline Roman Amalgamation

The gnostic Mithraists and Jewish Ebionites formed the very first Christians of the first century, with practices and beliefs based respectively on Gnostic and Judaistic rituals, symbols and practices. Pauline Christians dispensed with the difficult Jewish laws and became popular amongst gentiles, soon out-numbering the Jewish Christians, causing them to be secluded and eventually suppressed. Increasing literalism amongst roman converts then led the Pauline Christians to become obsessed with enforcing their literal interpretation of Christianity's original stories, causing another huge rift with older gnostic-style Christians. With Roman power behind their press and with the favour of Emperors, the Pauline-Nicene Christians wiped out the gnostics, annihilated the Arians after long bloody campaigns, and murdered and burnt the Marcionites and many other small sects, to leave themselves as the sole Christians within the Roman Empire, free to edit their own books to 'prove' how all their predecessors had been wrong. The three Cappadocian scholars promoted the Holy Spirit to the godhead to create a Trinity, which was codified strictly in to the Nicene Creed of 381, which went to careful lengths to disclaim against 'heresy'. Emperor Theodosius published a series of forceful edicts intolerant of all non-Nicene sects. This state of affairs persisted in the West for over a thousand years from the 5th century, causing mainstream Christianity to become completely ignorant of their own past.

2.10. Others (Melitians, Donatists, Monothelites)₂₁

• The Melitians and North African Donatists (4th-5th Century). These were both suppressed by proto-Nicene, and later, Nicene Christians. The Melitians would later ally with the Arians to attempt to rid themselves of their Nicene oppressors. The main cause of the schism was over some particulars of membership of the church, and whether or not lapsed Christians could rejoin, and their main opponent was Athanasius, who was also the persecutor of the Arians. The Melitians took to...
  

  “... holding unauthorized church services and ordaining clergymen without Athanasius's consent. His response was to send gangs of thuggish supporters into the (mainly Coptic speaking) Melitian districts, where they beat and wounded supporters of the Melitian leader, John Arcaph, and, according to Arcaph, burned churches, destroyed church property, imprisoned and even murdered dissident priests.”
  

  "When Jesus Became God: The Struggle to Define Christianity During the Last Days of Rome"
  Richard E. Rubenstein (1999)₂₂

• Monothelites (7th Century). These heretics were defined by the (seemingly common-sense) opinion that Jesus had only one will (not a divine will and a human will) but that he still had a divine and human nature. However the official Nicene, Trinitarian, position is that Jesus has two wills. This minor dispute, in the minds of the Nicene-Pauline Christian, was enough to spill blood over.
  

  “Theodore, Archbishop of Canterbury, called, in the year 680, a synod at Hatfield, consisting of all the bishops in Britain [d], where was accepted and ratified the decree of the Lateran council, summoned by Martin, against the heresy of the Monothelites. The council and synod maintained, in opposition to these heretics, that though the divine and human nature in Christ made but one person, yet they had different inclinations, wills, acts, and sentiments, and that the unity of the person implied not unity in the consciousness. This opinion it seems somewhat difficult to comprehend; and no one, unacquainted with the ecclesiastical history of those ages, could imagine the height of zeal and violence with which it was then inculcated. The decree of the Lateran council calls the Monothelites impious, execrable, wicked, abominable, and even diabolical; and curses and anathematizes them to all eternity.”
  

  "The History of England, Volume I" by David Hume (1688)₂₃

3. What Was the Original Christianity?

3.1. Who Were the First Christians?

We have described the Ebionites, the Marcionites, touched upon the Gnostics, and the Pauline Christians. Who were the original Christians? The Pauline Christians, Greek-speaking and with Roman power, rose to power and eliminated the others in the most un-Christian way. These were the late-comers to Christendom of these four groups. The methodical historian Bauer has studied this question at great length:

“Bauer proceeds by looking at certain geographical regions of early Christendom for which we have some evidence - particularly the city of Edessa in eastern Syria, Antioch in western Syria, Egypt, Asia Minor, Macedonia, and Rome. For each place, he considers the available Christian sources and subjects them to the closest scrutiny, demonstrating that contrary to the reports of Eusebius, the earliest and/or predominant forms of Christianity in most of these areas were heretical (i.e., forms subsequently condemned by the victorious party). Christianity in Edessa, for example, a major centre for orthodox Christianity in later times, was originally Marcionite; the earliest Christians in Egypt were various kinds of Gnostic, and so on. Later orthodox Christians, after they had secured their victory, tried to obscure the real history of the conflict. But they were not completely successful, leaving traces that can be scrutinized for the truth.”

"Lost Christianities" by Bart Ehrman (2003)₂₄

I will now summarize some contenders and explain if they could have been the true source of Christianity:

1. Ebionite Christians were the true Christians: Aramaic-speakers like Jesus and his apostles, they would have been the Jewish witnesses to Jesus' ministry and preaching. From this starting point, Jesus' teachings spread. They also, however, spread from Saul of Damascus, who renamed himself Paul and who preached an anti-Ebionite version of Christianity for the gentiles, which was much easier to follow and more popular.
2. The Marcionites were converts to Christ, who believed truly that he had been adopted by God at his baptism, and that he had come to abolish the laws of the Old Testament, thereby defeating the evil god of the Old Testament. Such gnostic beliefs may be the original form of Christianity as we shall see, but Marcionism itself can only be a later re-expression of it, and no historian thinks that the Marcionites were the original Christians.
3. Gnostic Christians: With stories, myths and beliefs that are exactly the same as Christian ones in many of the little details, gnostic beliefs manage to pre-date Christians ones by over 200 years. They understood what the stories of the NT really meant. Jesus didn't really exist, but was a collection of such earlier stories, rewritten in Greek, with Greek names. This is the approach taken by historians such as Freke & Gandy.

When the Roman-backed instance of Christianity went in search of the ancient centres of Christianity, they discovered to their horror that the Ebionites and Gnostics pre-dated them. Their un-Christian answer was to edit verses, burn books, invent doctrines such as the Trinity, arrest and harass the other poverty-stricken Christians until no opposition was left. The form of Christianity that we have inherited from the Roman Empire is far from what Christianity originally was, yet most modern denominations took Cappadocian-Nicene Pauline Christianity as their starting point (and few have moved far from it). Such a shame that this colourful history is not only abandoned, but is also mostly forgotten!

3.2. The Progression from Paganism to Christianity

Elements common to all types of the Christian religion that were common in previous Pagan mystery religions include much of the religious content of Christianity. All elements of Jesus' life such as the events around his birth, death and ministry were already parts of the myths surrounding other god-men of the time. Peripheral elements such as there being twelve disciples were similarly present in other more ancient religions and sometimes with an astonishing amount of duplication. First century critics of Christianity voiced accusations that Christianity was nothing but another copy of common religions.
All the actual sayings and teachings of Jesus were also not new, and much of the time speeches attributed to Jesus are more like collections of Jewish and Pagan sayings. Even distinctive texts like the Sermon on the Mount are not unique. If we remove all the content that Jesus could not have heard and repeated himself, there is nothing else left. If we remove the supernatural elements of Christianity that are copies of already existing thought and religion, there is nothing left which is unique! Even many of the sayings of subsequent Christians are not unique; Jesus appears to not have taught anyone anything that was not already present in the common culture of the time. This shows us that not only did Christianity follow on, as expected, from previous thought in history but that we do not even need to believe in God or supernatural events in order to account for the history of Christianity.

3.3. Christian Arguments Defending the Similarities of Christianity to Paganism

The fact that many pagan religions had many of the same dates, beliefs and practices as Christians led later Christians to denounce them as 'satanic imitations'. Theologians made the famous argument that the Devil had created these pagan religions so that people would think that Christianity was just a developed copy of them. The Cardinal Newman argued that (be it God or Satan's fiat) these pagan religions merely prepared people to accept Christianity. In other words, god made pagan religions in order to teach people Christianity, before revealing actual Christianity.

“To Newman, 'Pagan literature, philosophy and mythology were but a preparation for the Gospel.' His Protestant counterpart, Bishop Westcott of Durham, praised Greek thought for representing several stages in the unfolding of divine purpose. Gladstone determined 'to prove the intimate connection between the Hebrew and Olympian revelations', and told the House of Commons that Greek mythology had prepared minds for some of Christ's teachings. Kingsley agreed that it contained essential lessons in the human relationship with the divine.”

"The Triumph of the Moon: A History of Modern Pagan Witchcraft" by Ronald Hutton (1999)₂₅

Unfortunately, it seems that all such arguments are only half-truths. If there is a progression of human belief, then it implies that Christianity is itself not the final truth. Islam, for example, claims to be host to the teachings of the prophet that followed on from Jesus. If this progressive march continues, then Christianity itself may well just be a stepping-stone for another religion.

4. Literalist Christianity

This section is taken from The Causes of Fundamentalism, Intolerance and Extremism in World Religions, and Some Solutions: 4.1. Increasing Literalism is a Trait of Human Development.

Starting from cave walls, carvings, stone constructions, trinkets and hieroglyphs, the usefulness of the written word has pushed Human development onwards. Now the written word is almost ubiquitous with Human existence, and our massive databases of information and linked hypertext documents online are its current epitaphs. But although its practical utility in industry and technology speeds up change, the written word also has a tendency to slow down cultural change. Once something is codified in writing, it becomes "set in stone": the longer it persists, and the more people who read it out, the more it defines cultural truths. The more often it is written down, the harder it is to challenge. From this point of view, literalism and fundamentalism are clearly linked.
Superstition, religion and belief may have been the first things we as a species attempted to encode into displayable records. Or a very close second, after stories of hunting and practical life. The general trend is that religious texts have become more solid and interpreted more literally as time goes on. All religions have experienced, over time, increased literalism and legalism, even Buddhism and Hinduism. But it is Christianity and Islam that have taken to literalism most whole heartedly.
The literature of Jewish Christianity was often of a highly symbolic kind, with much wordplay and hidden meanings to be found in texts. Gnosticism and Roman Mystery religions, and then Gnostic Christianity, used an intensely non-literal and symbolic form of writing. Text was two-tier. The outer religion was the kind seen by the populace. It was a simple story, a myth, often a rewriting of existing myths in to a more modern form or using updated characters. The inner religion was revealed to initiates. They were told the true meaning of the story and what each character, event, word and object in it represents and means. The illusion of the story of a literal event was revealed to be meaningless and ahistorical. Gnostic Christianity, closer to these, was suppressed by the fledgling roman Christian church, and the oppressor was naturally more literalistic and legalistic. Pauline Christianity - the type that prevailed - accepts Christian texts purely on the basis of the outer religion, the outer meaning: the literal text.

“The history of Christianity - from the death on the cross onwards - is the history of a gradual and ever coarser misunderstanding of an original symbolism.”

"The AntiChrist" by Friedrich Nietzsche (1888) [Book Review]₂₆

With the Council of Nicea, and onwards, an authoritive collection of texts was compiled (canonized), and as was already customary, competing texts were burnt, suppressed, and heretics who stood by them were killed and vanquished. This is a continuation of the process of literalisation -- a final complete authorized version is inherently a more legalistic formation than a loose and open canon. From the 4th century, the literalist written word in Christianity grew to be utterly dominant and had paved the way for fundamentalists ever since.
I've already written of the deleterious effects of such literalism on science and knowledge:

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The stubborn stance against science and real-world knowledge in Christianity stems from the very founders of that religion. Take Tertullian, one of the great and powerful Christian speakers of very early Christianity, who in 200CE was defending Christianity against its critics. 'Before he closes his defense, Tertullian renews an assertion which, carried into practice, as it subsequently was, affected the intellectual development of all Europe. He declares that the Holy Scriptures are a treasure from which all the true wisdom in the world has been drawn; that every philosopher and every poet is indebted to them. He labors to show that they are the standard and measure of all truth, and that whatever is inconsistent with them must necessarily be false'₂₇. And what a terrible legacy became of that mode of thought: it is only true if it says so in the Bible. The hallmark of ignorant, dangerous barbarianism and fundamentalism.
Thankfully for the study of truth, the process of secularisation has diminished the strength of religion across the West, and since the Enlightenment, when religious institutions started to lose control of public life, education continues to act as an anti-religion force in the world: the more educated a person is, the less likely they are to be religious. Education is the key to leading successful, happy and above all, a meaningful life devoid of nonsense. The future looks bright for many. Although Europe excels (in a patchy way) in all-faiths education where religions cannot stamp their particular dogmas over science education, this is not the case in much of the rest of the world, so there is much work yet to do in combatting anti-science religiosity.”

"Science and The Scientific Method: Its Character and History: 9.1. In the Western World" by Vexen Crabtree (2014)

Jesus may well have started out as the creation of Gnostics, who were telling a symbolic story with many parables, much mysticism, and little historical truth. But this story paired well with the Jewish community who were expecting an actual Messiah to arrive. Whether or not Jesus existed as an actual person, it soon transpired that the generations after his supposed existence came to believe in him has an actual person. Although St Paul wrote exactly like a gnostic in all his early writings, Greek authors forged seven epistles with a strong literalist slant, which they then included in the Christian Bible.

“Paul's epistles make up 7 of the Books of the Bible. Also, six more were written in Paul's name at later dates (in some cases some believe the text was written over 80 years after Paul's death). There are 13 epistles (epistles) which were canonized into the Bible under the name of Paul. The authentic writings are gnostic, whereas the later pseudonymous texts are more literalist and misogynistic.”

"St Paul - History, Biblical Epistles, Gnosticism and Mithraism" by Vexen Crabtree (1999)

5. The Evolution of Religions: The Bad Boys Survive at the Expense of the Nice

Religions compete for believers. They compete for influence because the more influence and exposure they have, the more believers they will get. This competition doesn't have to be conscious, or on purpose, it just happens to be that popular religions that are happy with power will prosper, accidentally inhibiting competing religions. There is interplay not only with believers, but with non-believers who have power. Religions that fall foul of politics are very frequently eradicated or ridiculed into extinction, whereas religions that appear to rulers to support the status quo can prosper.

“It is not surprising that the dominant motif in the world's major religions has been a hierarchical one - the ruling powers of most societies understandably promote authoritarian religious ideologies and suppress the egalitarian beliefs. Early Chinese culture, for example, had two competing traditions: that of K'ung-Fu-tzu, which emphasized the need for strict social hierarchy and respect for elders and political authorities, and that of Mo Ti, who promoted an egalitarian ideology and ridiculed the followers of K'ung-Fu-tzu for their "exaggerated" emphasis on authority. The first tradition was institutionalized as Confucianism and became the official state religion of the emperors, whereas the second precipitated a relatively unstable popular movement that was almost lost over the centuries.”

"Gods in the Global Village" by Lester R. Kurtz (2007)₂₈

So it came to be that the literalist, nastier forms of Christianity survived the first few hundred years of Christian history, because it appealed to a wider number of people. It didn't require such things as circumcision or strict dietary laws. Literalist Christianity held power in Rome and it is no coincidence that it happened to preach a strict hierarchy, instructing slaves to serve their masters, instructing for taxes to be paid ("give to Caesar what is Caesar's" - Matthew 22:21) and instructing that people subject themselves to their governors (Romans 13:1). This form of Christianity, as we have seen, was oppressive, combatitive and organised, wiping out its nearest competitors, which was other forms of Christianity, with help from the institutions and Emperors of the Roman Empire. This conflict became legendary; pagan leaders, historians and competing religions all commented on the propensity for Christians to be found mostly engaged in battles with other Christians. Qur'an 5:14-15 asserts that enmity and hatred between Christians is a punishment from God for their "abandoning parts of God's message".₂₉
This survival of the fittest was not just relegated to Christian history, but as Christianity aged and further divisions became apparent, the conflicts continued. Read on.

6. Lost Christianities of Later History

“In the twelfth century the orthodox Church had become weak and open to serious criticism among an illiterate and largely impoverished population. They attended services that were conducted in Latin and were therefore incomprehensible to many. They saw the clergy living in luxurious surroundings and supporting concubines and generally began to regard the Church establishment as corrupt. As a result of this, Christian cults built from among their own began to prove more attractive. The Church viewed this with considerable alarm [...] and it responded with the enormous muscle that it had at its disposal.”

"Cults: Secret Sects and Radical Religions" by Robert Schroëder (2007)₃₀

6.1. The Cathars / Albigenses (12th-15th Century)

The Marcionites of the 2nd century were lost to oppression, however, their form of Christianity was not completely eradicated. The Paulicians (followers of Marcion) and Manicheans fused to form the Bulgarian Bogomils, who like their founding sects, were oppressed. But the Bogomils were carried by Crusaders to Italy and France, where their gnostic-seeming beliefs flourished and were widely accepted.

“The most interesting, and also the largest, of the heretical sects were the Cathari, who, in the South of France, are better known as Albigenses. [Their beliefs] were widely held in Northern Italy, and in the South of France they were held by the great majority [...]. The cause of this wide diffusion of heresy was partly disappointment at the failure of the Crusades, but mainly moral disgust at the wealth and wickedness of the clergy. [...] The Church was rich and largely worldly; very many priests were grossly immoral. [...] The more the Church claimed supremacy of religious grounds, the more plain people were shocked by the contrast between profession and performance. [...]
It seems that the Cathari were dualists and that, like the Gnostics, they considered the Old Testament Jehovah a wicked demiurge, the true God being revealed in the New Testament. They regarded matter as essentially evil, and believed that for the virtuous there is no resurrection of the body. The wicked, however, will suffer transmigration into the bodies of animals. On this ground they were vegetarians, abstaining even from eggs, cheese and milk. They ate fish, however, because they believed that fishes are not sexually generated. All sex was abhorrent to them [...]. They accepted the New Testament more literally than did the orthodox; they abstained from oaths, and turned the other cheek.”

"History of Western Philosophy" by Bertrand Russell (1946)₃₁

The Cathars attracted increasingly violent attention from the Roman Catholic Church.

“The Catharists who came in for the full might of the Inquisitor's wrath. [...] The cult attracted large parts of the population of southern France before it spread to Italy, Spain and Flanders. [They] took up the banner of the earlier Gnostic sects like the Manichaeans. [...] Persecution of the Catharists was launched on a horrific scale in 1208, following the assassination of a papal legate in Toulouse. This was identified as a Catharist conspiracy and a Crusade was mounted against them, headed by Simon de Montfort.
Some 200,000 zealots embarked upon a twenty-year campaign of attrition, funded by the Catholic Church, during which large parts of southern France were laid waste. Essentially, their movement had become too large and too popular to be tolerated. In one dreadful reprisal the entire population of the town of Béziers was slaughtered. [...] Those of the Catharists who were lucky enough to be left alive fled to the Balkans. They continued until the fifteenth century, after which the majority were slowly absorbed into the Muslim faith.”

"Cults: Secret Sects and Radical Religions" by Robert Schroëder (2007)₃₂

6.2. The Waldenses (12th Century)

Peter Waldo was a rich merchant who lived Lyons, France. In 1170 he declared a 'crusade' for the return to the observance of the law of Christ. He gave everything he had to the poor and founded the 'Poor men of Lyons'. In an era where the corruption and power of the Church affected everyone, this ascetic, humble and powerless Bible-based movement adhered strictly to virtuous and moral codes of conduct and they proved immensely successful. "At the start they were active through much of the south of France and Lombardy, but their cells extended to Germany and Italy in the decades after the death of Waldo"₃₃. Pope Alexander III had given them papal approval to preach "but they inveighed somewhat too forcibly against the immorality of the clergy, and were condemned by the Council of Verona in 1184"₃₄ and were excommunicated₃₃. But they did not falter.

“They decided that every good man is competent to preach and expounded the Scriptures; they appointed their own ministers, and dispensed with the services of the Catholic priesthood. [...] All this heresy alarmed the Church, and vigorous measures were taken to suppress it. [Pope] Innocent III considered that heretics deserved death, being guilty of treason to Christ. He called upon the king of France to embark upon a crusade against the Albigenses [which affected the Waldenses also], which was done in 1209. It was conducted with incredible ferocity; after the taking of Carcassonne, especially, there was an appalling massacre.”

"History of Western Philosophy" by Bertrand Russell (1946)₃₄

“By the middle of the thirteenth century, however, many of the Waldensians were imprisoned and those who were not burned as heretics were forced to flee to remoter regions of the Italian Alps, where their remnants survived. In the sixteenth century, they formed a predictable but loose alliance with the Calvinits and suffered intermittent persecution at the hands of the Catholic Church until the seventeenth century. Waldensians still exist in the North Italian region of Piedmont.”

"Cults: Secret Sects and Radical Religions" by Robert Schroëder (2007)₃₅

7. Modern Christianity is Still Very Varied

Professor Bart Ehrman opens his book Lost Christianities with the statement that "it may be difficult to image a religious phenomenon more diverse than modern-day Christianity"₃₆ (excepting, he explains, that ancient Christianity was even more diverse).
One major aspect of Christianity can be said to be the cause of its success: there is a lot of widespread difference in belief across Christian denominations. As perhaps the most fragmented and violent religion in history, Christianity has become broken into countless different denominations and churches, all of which call themselves Christian. Many denominations are intolerant of each other's beliefs. For example any Atlas will tell you that Congo or Angola is dominantly Christian, "and this is true in the sense that many are baptised and go to church. However, people in Congo and Angola constantly talk about ancestors and witches and perform rituals to placate the former and restrain the latter" and this is not something most other Christians ever do₃₇. It can be said that as all these denominations cover such a wide range of beliefs that it is obvious that many people can call themselves a Christian because they're bound to share some beliefs with some denominations. But, merely knowing that they call themselves a Christian gives us very little actual information about their beliefs, as Christianity is such a diverse religion.