Mohammed was the most successful cult leader in history. His atavistic, bronze-age inspired barbarity is still killing innocents 1400 years after his death. This signal fact is a rather remarkable testimony which affirms the human penchant for the irrational, the abstruse and the decidedly savage. Why anyone would believe that a man who led 60+ military expeditions and conducted acts of violence including war, murder and rape, every six weeks over a 10 year period to make himself King of Arabia, is a 'prophet' of a 'religion', 'dedicated to peace'; is surely one of the greatest mysteries in human history. I can't imagine one single Christian supporting the church of Christ, if Christ had been Muhammad. Not one.
Most people assume the Koran is about 'God'. It is not. First Allah is al ilah or the Lord. It references Muhammad's tribal deity Baal the ilah of Mecca. Second, the Koran is only 1/3 of the Moslem trilogy. The Hadith which are the basis of Sharia Law, are entirely about Muhammad and they are [albeit in a repetitious manner] some 60% of the Moslem trilogy. The 3rd book of Islam, the Sira or biography of Muhammad [see Ishaq 'A Life of Muhammad'], is about 20% of the total and over 70% of that text is devoted to Muhammad's Jihad against the Kufars including Jews, Christians and pagans. We thus have over 75% of the total works explaining Islam or the cult of submission, about its founder and most of it concerned with the Kufar, erroneously translated as 'Unbeliever' but which in fact is a word which denotes a sub-human.
In roughly 13 years from 610 to 623 AD, beset by visions and dreams, Muhammad's preaching about the sole monotheistic power of Baal or the ilah of Mecca [his last name was Abdullah, or slave of Allah]; attracted at most 150 converts, many of them family and slaves. After being expelled from Mecca and finding refuge and allies in Medina, from roughly 622 AD until 632 AD or in a mere 10 years, Muhammad's 'preaching' turned to war and violence, and he conquered with his brigands all of Arabia. The message was clear. Islam would be spread by the sword, through the shedding of blood and forcible submission to Muhammad's rule. This theme has not changed one iota over 1400 years.
Muhammad outlawed other idols including the Sun goddess Allat, the moon and Venus [Manat and Uzza]. Shrines of idolatry were torn down. Rituals established by his tribe the Quraysh were simply upheld and implemented as part of Allah's [read Muhammad's] program. Ritual prostrations, prayers, poems, circling the Kaba or cube of Mecca, praying and drinking from a well called Zam Zam, throwing stones at pillars or little devils, kissing the black asteroid rock in the Kaba...all of these extant expressions of submission to Muhammad are found in pagan Arabian culture, long pre-dating the rise of Muhammadism.
Judaism and Christianity, which in a broken form had been imbibed by Muhammad, were superseded by the 'new' revelations to Muhammad. In the Koran and Hadith Muhammad calls the 'Peoples of the Book', a derisive term used to describe the wayward, corrupt Jews and followers of Christ; as beneath the contempt of the moon idol Allah; because they had expunged from their 'Book', the prophecy that Muhammad would arise as the greatest and last prophet.
Even today, many Moslems still maintain that Christ prophesied the life of Muhammad and declared that he would be the most important of God's messengers. Similar ignorant claims redound about the Old Testament. Of course no such pronouncements were ever made. But the claim dates back to Muhammad's time in Medina, and his inability to persuade Jews or the small number of Christians living there; that he had any legitimacy whatsoever. So he declaimed that the Jews and Christians had changed their Books, had corrupted 'Allahs' original message, and thereby denied Muhammad his rightful status as the final and greatest of the messengers. The Koran is littered with such declamations as are the Hadith.
Sura 9:63 summarizes the cult of Muhammad:
“Know they not that for those who oppose God and His Apostle, is the Fire of Hell? - wherein they shall dwell. That is the supreme disgrace.”
Jews and Christians who 'changed their scripture' to avoid recognizing Muhammad as their rightful leader are doomed in this life and the next. Baal and Muhammad said so. Western Phds would declare this to be 'science' and proof that Islam is tolerant.