In this fascinating study of the origins of Islam, historian Mondher Sfar reveals that there is no historical, or even theological, basis for the orthodox view that Muhammad or his earliest followers intended the Koran to be treated as the inviolable word of God. With great erudition and painstaking historical research, Sfar demonstrates that the Koran itself does not support the literalist claims of Muslim orthodoxy. Indeed, as he carefully points out, passages from Islam's sacred book clearly indicate that the revealed text should not be equated with the perfect text of the original "celestial Koran," which was believed to exist only in heaven and to be fully known only by God. This early belief helps to explain why there were many variant texts of the Koran during Muhammad's lifetime and immediately thereafter, and also why this lack of consistency and the occasional revisions of earlier revelations seemed not to disturb his first disciples. They viewed the Koran as only an imperfect copy of the real heavenly original, a copy subject to the happenstances of Muhammad's life and to the human risks of its transmission. Only later, for reasons of social order and political power, did the first caliphs establish an orthodox policy, which turned Muhammad's revelations into the inerrant word of God, from which no deviation or dissent was permissible. This original historical exploration into the origins of Islam is also an important contribution to the growing movement for reform of Islam initiated by courageous Muslim thinkers convinced of the necessity of bringing Islam into the modern world.