The best book to read would be the bible, in its entirety. That is what made me an Atheist. I was a Southern Baptist sunday school teacher, in the choir, played handbells, the whole nine yards. I was deeply religious. I studied the bible in depth and was so disturbed by what I read I began to question Christianity. I then joined a more progressive denomination and became a youth minister. (They didn't take the bible literally.) Even that didn't put me at peace. Even when I tried to look at the bible from a philosophical standpoint, I knew the whole religion was based on racism and hatred and I could not in good conscience associate with such evil. I walked away and found out how wonderful it feels to be free.
The bible is a vile and evil book. Few Christians have actually read the whole thing. They read what they are told to read and skip the nasty stuff. Once you read it for yourself and find all the contradictions and see the purely evil things God has done, a decent person cannot remain a Christian. The basis for religions that worship deities is just too idiotic to ignore once you really start searching for truth. Once you care more about truth than you do being accepted and popular, you will find truth.
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