I grew up in a religious household. I don't mean that we were Fundies or any such nonsense, just that we were a typical middle-class family living in a "Leave It to Beaver" suburb and we attended church and Sunday School every week until I was 10 years old.
My mother taught Sunday School for years and wanted us to grow up as Protestants, as she said, "To give you a sense of reverence," although why this was automatically supposed to be a good thing, I don't know. My dad worked for the Government and his bosses felt that having the family in church was good PR. So we went. I and my siblings learned all the usual stuff about the Creation, the Fall of Man, God's picking the Hebrews as his favorite team, the coming of Jesus and the whole Passion Story.
And I believed. I remember lying in bed at night pleading with God to forgive my sins should I not wake. I held on to the belief that nothing i did in this world was important compared to the world to come! Yes, sir, let the school bullies pick on me, God's got their numbers!
My deconversion occurred as it often does. I had a Bible and had picked through it, but one day, on a camping trip, I started to really READ it.
I couldn't believe it. The lack of logic in God testing man when he KNEW what the outcome would be, the war crimes committed by the Hebrews in the name of their god, the stories that were obvious mythology, the "stories of Jesus" which I began to realize were preposterous.
But the thing that angered me was the obvious hatred of women and championing of slavery in this book. Women were nothing to the scribblers of the Bible— women were too inferior to teach men, were to keep their mouths shut and not ask questions in church, etc. I wondered what in hell was so attractive about this trash to my mother and women like her, who devoted their time to a religion that despised them and a God who cared nothing for them!
And I understood miracles thereafter: I had NEVER had a "prayer answered" in ANY way that couldn't be accounted for by normal, mundane agencies. If I got a job, it was because I DID IT, not because I prayed for God to give me one; I realized that if Justice was to prevail, we all have to abandon the view that vengeance is God's and he will repay. He won't, sorry.
By the time I was thirteen, I had lost my belief in the Abrahamic nonsense (and yes, that means that I concluded that Islam is a load of rubbish, as well.)
Today I look back on the childish, empty-headed belief system I swallowed as a kid, and I know that there is no God out there of the type spoken of in the Bible. I shake my head at my stupidity.
I still read the Bible, but for what I think it is: writings by a primitive people who were trying to make sense of the world around them and find a way to fit themselves into it. From that standpoint, the book is a good one.
So in closing, let me say that I am an example of the fact that nothing will turn you into an unbeliever as quickly as reading the source material.