The skeptic says that a number of Western (German, British, American) experts in Islamic history have basically proven that the Qur’an did not come all of a sudden, but rather was a slow project developed over several generations, and made use of various Arabic, Syriac Christian and Jewish sources. Do you have any information about this, and how it may be refuted, both generally and in its specific allegations?
Answered by Sharif Randhawa (Researcher at Bayyinah Institute, owner of Qur’anic Musings blog)
Very briefly, this is an extremely fringe view and even some of the handful of scholars who belonged to this school of thought (e.g. Michael Cook, Patricia Crone) no longer hold to it. There is ample material refuting this thesis.
For example, if one wishes to make use of the sources from the same Western academic setting, see a number of essays in the work The Qur’an In Context, ed. Angelika Neuwirth, Nicolai Sinai, and Michael Marx: http://serdargunes.files.wordpress.com/2012/10/neuwirth-quran-in-context.pdf. There have also been some recent manuscript discoveries that blow this theory out of the water.