Historicity of Muhammad

The earliest Muslim sources of information for the life of Muhammad is the Qur'an, which gives very little information and whose historicity has been questioned. Next in importance is the sīra literature and Hadith, which survive in the historical works of writers from the second, third, and fourth centuries of the Muslim era (c. 700−1000 AD). There are also a relatively small number of contemporaneous or near-contemporaneous non-Muslim sources, which confirm the existence of Muhammad and are valuable both in themselves and for comparison with Muslim sources.

The main Islamic source on Muhammad's life are Muslim sources written in Arabic, which include the Qur'an and accounts of Muhammad's life written down by later Muslims, based on oral traditions. These sources are known as sīra and hadith.

According to traditional Islamic scholarship, all of the Qur'an was written down by Muhammad's companions while he was alive (during AD 610-632), but it was primarily an orally related document. The written compilation of the whole Qur'an in its definite form as we have it now was not completed until many years after the death of Muhammad.

Modern scholars differ in their assessment of Quran as a historical source about Muhammad's life.

According to the Encyclopedia of Islam, the "Qur'an responds constantly and often candidly to Muhammad's changing historical circumstances and contains a wealth of hidden data that are relevant to the task of the quest for the historical Muhammad." In contrast, Solomon A. Nigosian writes that the Qur'an tells us very little about the life of Muhammad.

F.E. Peters states, "Few have failed to be convinced that what is in our copy of the Quran is, in fact, what Muhammad taught, and is expressed in his own words... To sum this up: the Quran is convincingly the words of Muhammad, perhaps even dictated by him after their recitation". Peters argues that "The search for variants in the partial versions extant before the Caliph Uthman’s alleged recension in the 640s (what can be called the 'sources' behind our text) has not yielded any differences of great significance." .

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