I'm still reading Moojan Momen's book The Phenomenon of Religion. A Thematic Approach (Oneworld Publications, 1999), and blogging about what I find interesting in the book. Some time ago I was reading about Islam. Now I want to extract a longish excerpt from Momen's book on the same topic, specifically the Hadith, or Traditions about the alleged sayings and doings of Muhammad the alleged prophet:
Of course, Muslims themselves have always recognized problems regarding the authenticity of the Hadith literature. Acknowledging that many Traditions relating to Muhammad were forged in the early period, they developed a whole branch of Islamic science that sought to distinguish between the true and the forged Traditions. They examined the line of transmitters of each Tradition and tried to ascertain the reliability of each person in the chain. They also examined the line as a whole and determined whether the individuals in the chain of transmission could have been in contact with each other.
Modern Western scholarship, however, examining critically the earliest surviving documents, has cast a much more fundamental doubt over the Hadith literature. The first to raise questions about the traditional version of the rise of the Hadith literature was Ignaz Goldziher. He showed that up to three centuries after Muhammad, many individuals, political parties and sectarian movments within Islam were manufacturing Traditions that supported their claims and positions. These Traditions, claiming to be on the authority of Muhammad, gave each faction legitimacy and authenticity.
Joseph Schacht took this line of research further. He showed that the schools of Islamic law that arose were in fact the result of differing sets of customary law in such towns as Medina and Kufa. These centres established what had been the customary tribal law from pre-Islamic times in their area by incorporating it into the Holy Law. It was only at a later date, when it became the norm to trace all law back to the Prophet Muhammad, that there evolved numerous Traditions relating these practices back to him. In this way the customary law of each of these places became enshrined in the Holy Law, the Shari'a of Islam.
We should not see this process of the retrospective attribution of customary practice back to Muhammad as the activity of malicious forgers. Rather, these were the actions of sincere and pious men who regarded their views as the correct Islamic standards. From this it was only a short step to being certain that the Prophet would have acted in the same way if faced with the same situation; and then another short step to saying that the Prophet did act thus; and then yet another short step to creating a Hadith that confirmed that he did act thus.
(Pp. 325 - 326.)
Momen goes on to talk about Wilfred Cantweel Smith's hypothesis about the the origins of the term Shari'a, but since it is apparently not as well established as the above, I won't quote that part.