Some say that what he said was written on Palm leaves, stones, parchments and other things (I forget now). However, it seems there were collections of writings amongst people who knew him and were in many dialects. Eventually it was ordered that all the writings and memories were to be compiled in to one copy with all others burned.

It is said that one verse, 33:23 was found with only one man:-

'Among the Believers are men Who have been true to Their Covenant with Allah, Of them, some have fulfilled their obligations to Allah, And some of them are waiting"

So, argument will rage for ever as to whether everything he said was written down, how accurate it was and whether what was eventually written down as the one and only version had inclusions from others or had omissions both accidental and deliberate.