Putting my review here, in case the tax-dodgers at Amazon get grumpy and refuse to publish it.
"Lots of interesting information about debates within Judaism, Christianity and Islam, but a rather partial account that focuses on the intellectual content of these debates rather than their social, political and institutional context. So lots about the debate within Orthodox Christianity about whether God has one substance, or whether he is three or one person, but nothing about the process whereby Christianity became the state religion and how that related to the need for a single position on doctrinal matters. Similarly with Judaism - you'd think Hasidism emerged just as a reaction to intellectual currents within rabbinic debates; the massacres of the 1640s, and even the name of Chmielnicki, don't even figure.
Perhaps more important for this atheist reader, there is a sleight of hand which is barely acknowledged. The God worshipped by Judaism, Christianity and Islam is a personal God, and the idea for him emerged from a tribal deity that was very much associated with some human and some super-human characteristics. The God of the philosophers - some distant first cause without any personal or human characteristics - is a very different entity (or as she would have it, not actually an entity at all, but something more profound). It might make sense to build a set of social institutions around placating and 'worshipping' the personal God, but the second one can only be contemplated. Worshipping it makes no sense. And yet religious clever-clogs, and people who make a living out of religion, somehow manage to conflate the two. It would be unfair to say she doesn't write about this, but I didn't see it satisfactorily addressed.
That said, there were some really good parts in the book. This is the first time I've ever understood why it was so important for the Greeks to have those rows about the essential nature of the trinity - it was an argument about the limits of human understanding and cognition, which is important for us now in relation to cosmology and physics, but the Greeks didn't have the instruments, so they made it a discussion about God. And she also touches on the way that the Romantics replaced a sense of the divine with a sense of the aesthetic, particularly in relation to nature. As one who only has what other people call spiritual feelings in relation to this sort of thing, it's nice to know it has a lineage, and it actually made me want to go and read Keats and Wordsworth.
So all in all, time well spent, despite a nagging feeling of dissatisfaction about the book."