I would not recommend this work for someone seeking a safe bridge from one of the monotheisitic religions to atheism. I found it a bit too strident for that purpose. To condemn those faiths for deeds that were done in 312 or even during WWII doesn't help the traveler looking for a safe haven in today's increasingly secular world. I would rather he'd spent more time discussing the positives of leaving the devisive, irrational worlds of faith behind for the reasoned world of common humanity.
However, for someone who has already crossed that bridge, there are some worthwhile nuggets to be mined here and the Kindle edition price was quite reasonable.
I have some minor quibbles with his definition of an atheist. An a-theist is simply one who lacks faith in a god. It is not as the author or the Oxford dictionary would have us believe that it is someone who believes that God does not exist. It is a minor but important distinction because to believe that God does not exist is just another form of faith—it is not based on evidence. Being an atheist does not tell you much about what that person believes or values, only that they do not believe in a god. An atheist can also be an agnostic. He may lack a belief in a god (atheist) and at the same time lack knowledge or evidence that some cosmic force might somehow have caused the Big Bang, and therefore still be open to that possibility (agnostic). Thus they are not separate categories as is often assumed.
Being and atheist and an agnostic also does not tell you much about the person's philosophy or value system. For that you need to ask more questions. Many atheists and agnostics are secular humanists, and that does tell you a lot about them if you care to take the time to find out what secular humanists are all about.
Unfortunately, this author does not get into this at all. Dan Barker does a much better job of this in Godless: How an Evangelical Preacher Became One of America's Leading Atheists
and Bart Ehrman does a better job of documenting and sourcing the many contradictions in the New Testament in his Jesus, Interrupted: Revealing the Hidden Contradictions in the Bible & Why We Don't Know About Them
. For that person looking for a friendlier bridge to cross from faith to reason I recommend these two, particularly the latter, over this book