Islam [Abrahamic, 610 AD] 1.3 billion adherents [Wikipedia | Britannica | Beliefnet]

Islam is a monotheistic religion originating with the teachings of Muhammad, a 7th-century Arab religious and political figure. Muslims believe that God revealed the Qur’an to Muhammad, God’s final prophet, and regard the Qur’an and the Sunnah (the words and deeds of Muhammad) as the fundamental sources of Islam. They do not regard Muhammad as the founder of a new religion, but as the restorer of the original monotheistic faith of Abraham, Moses, Jesus, and other prophets. Islamic tradition holds that Judaism and Christianity distorted the messages of these prophets over time either in interpretation, in text, or both.
Almost all Muslims belong to one of two major denominations, the Sunni and Shi’a. The schism developed in the late 7th century following disagreements over the religious and political leadership of the Muslim community. Roughly 85 percent of Muslims are Sunni and 15 percent are Shi’a. Muslims consider the Qur’an to be the literal word of God; it is the central religious text of Islam. Muslims believe that the verses of the Qur’an were revealed to Muhammad by God through the angel Gabriel on many occasions between the years 610 and his death on July 6, 632.
Islam considers itself to be the supreme religion and therefore Muslims must not place themselves in a position inferior to that of the followers of other religions. Pursuant to this principle, Muslim women may not marry non-Muslim men, non-Muslims may not inherit from their Muslim relatives, and a testimony of a non-Muslim is inadmissible against a Muslim. A non-Muslim who insults Islam must be put to death, according to most schools of Islamic jurisprudence, or flogged and imprisoned, according to others.
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