It must also be remembered that Muhammad recited the 'revelations' making up the Quran to his companions with instructions that they should memorise them.

There is uncertainty as to when these were committed to paper with many scholars suggesting that this could be as long as 100 years after Muhammad's death.

What appears to be beyond doubt is that Islam recognised 'good' Christians and Jews as 'People of the Book'

3-113 Of the People of the Book are a portion that stand (For the right): They rehearse the Signs of God all night long, and they prostrate themselves in adoration