Another book, actually written from a Christian perspective by former bishop N. T. Wright is "The Challenge of Jesus". This book challenges much of the narrative of Jesus and encourages the church to get back to some facts in their belief system, which caused me to question much of what I had ever been taught. It was one of the first books at the beginning of my deconversion, especially since I was willing to read it. Just see this negative Amazon review for an idea of its power.