How did St John of Damascus view Islam? John of Damascus was one of the first Christian authors to write about the rise of Islam shortly after the time of Muhammad. I am fascinated by this man but I can't seem to find enough info about this subject on the Internet. I was wondering how exactly did he view Islam in his writings?
You may find a book that shows his writing about the followers of Islam On Heresies (see 101) by St. John of Damascus .  

The writing of St. John of Damascus basically runs like this: (Actually he does not really say that much in depth, or from argumentation from scripture but still it is interesting)


He mentions Mohammed and his book
He pokes fun at the idea that a man can claim to receive such a book without any witnesses
The main heresy in Mohammed's book is that it denies Jesus to be God
He says Islamists accused the Christians at that time of idolatry because of how they venerated a cross and he in turn questions their veneration of the black stone at Mecca
He accused Mohammed of legalizing polygamy
He proceeds to make fun of some strange additional books written by Mohammed  especially the first about a Camel that went to heaven
He returns to the subject of their opposition to veneration of images, Saints , Mary, and rejection of Priesthoods.
Finally he states the traditional doctrine of the Trinity to rebuff their main error.