Yes, I feel the same. It's hard for me to think of the Qur'an as being a compilation as I am so conditioned to see it as Muhammad's (God's
) words, even though I had come across such a view way back when I was at SOAS, from my then Tutor, Dr. Wansbrough in his book Qur'anic Studies. But I rejected it outright then. I am more open to the idea now, but where is the hard evidence?
The Qur'an does seem like a jigsaw at times with blocks of text repeated in slightly different forms here and there and I can easily imagine how it could have been mixed and matched and added to and taken away from before it was set in stone generations after Muhammad.
I think the traditional view is not so different from the revisionist views if you think about it. Both the traditional and modern views see the Qur'an as a composite slowly produced over a LOOOOONG period of time (decades for both views) in radically different social circumstances that resulted in radically different directives stated in the text (traditionally, pagan Mecca v. Judao-Mohammedan Medina). Both the traditional and modern views see the Surahs as including later interpolations (for example, Surah 74:31, even Muslim tradition recognizes the blatant interpolation, or the end of Surat an Nisan, 4:176 ... nobody could think this was an original text ... so to explain, that, Muslims just argued these individual ayas were received later as separate revelations to Mohammed). Both the traditional and modern views see the "Mushaf" as a sort of composite formed by committee out of disparate materials after Mohammed's death.
Likewise, the many straightforward contradictions in the Qur'an (one moment wine is great, the next it's a sin) had to be explained away by a concept of successive revelations in which the older conflicting texts were later replaced by new revelations. One part of the Qur'an preaches peace and love towards the Jews, other parts are bitterly anti-Semitic; why, well Muslim tradition came up with the explanation that Mohammed was betrayed by the Jews at one point during his revelations, specifically at Medina. I think traditional Muslims may not recognize how artificial this device is, how it's a way of attempting to integrate the many strange disjunctions in the surahs and try to account for them as if they were produced by a single individual.
There are even hadith recording how scribes added text to improve the rhyme, and how Mohammed heard their version recited back to him, and 'adopted' it as the Qur'an.
Where they differ is that the traditional view argues that the work is unified in the life of a single Arabian prophet, and that it was flawlessly orally transmitted (sort of) apart from its textual form. The modern view would argue that is a tendentious later argument imposed on the text, and if you look at the text, it is radically heterogeneous (compare it with any other work of Near Eastern religious literature that is traditionally assigned to a single author, for example, and with the exception perhaps of the Gathas there is none so heterogeneous).
So this is the strongest evidence that it's a composite text -- it's essentially undisputed that it HAS to be a composite text assembled by multiple hands over a long period of years, the question is just what that process of composite assembly most likely consisted of, and whether the text as we know it all fits comfortably within the traditional account of the life of an Arabian prophet, reflecting just his words as reliably recalled by his associates before being written down, with no other material. For many reasons, I think that account --- I describe it as an unlikely hypothesis about the textual origin --- has been shown thoroughly defective and unreliable. Thus the burden of proof falls on the other foot ... we should no more take a believer's account of the Qur'an's origins written 200 years later as reliable than we should do the same for an account of a NT Gospel's origins written 200 years later.
I think it is very beneficial to sit down with a modern translation of the Qur'an and really think through what it is actually saying, while 'bracketing' the traditional explanations. Treat it as you would *any other religious text* that is the object of study. I think this is probably difficult for both believing Muslims and traditional scholars, to set aside the traditional interpretive apparatus and look at the text fresh and critically. One of the first results of this process will be that the text is consistently baffling or unclear, but this is just a reality that must be dealt with.