Robert Wright has written a tome of information dealing with the idea of God in The Evolution of God.
Wright takes us back to the earliest ideas and conceptions of gods for the hunter/gatherers and walks us up to Biblical times through Islam.
Before tackling El and Yahweh, Wright explains how god's functioned in the different ancient cultures.
The information given in these early sections is worth the price.
The real ride comes when he begins discussing Israel and the gods of the Middle East.
Wright doesn't believe certain biblical characters & stories are real (i.e. Moses and Elijah's battle with the Baal worshippers).
Then, to add more TNT to the explosive assertions, Wright decides that, based on evidence and speculation, Jesus was not a promoter of "Love your enemies", Jesus did not care about those outside of Israel.
I can see how many people would want to write nasty things about this guy. Which is a shame.
If you claim to be a Christian, the value of this book may come from Wright's different perspective of The Bible.
Believe in God, don't know if you can know God, or just flatly deny His existence, The Evolution of God is well worth a couple weeks of your time for exploration.