I read the Bible cover-to-cover twice. It didn't make me an atheist, but it did cure me of being a Christian. I suppose I was an 'agnostic theist' for the next twenty-or-so years after that.
As far as I know, there hasn't been a study on whether atheists in majority Christian countries are more likely to have read the Bible in its entirety than the Christians in their country. There was a Pew Survey on Religous Knowledge in the US that indicated atheists are more knowledgeable than any other group about religion in general (followed closely by Jews), but I think fundamentalist/evangelical Christians came out as most knowledgeable about their own religion.
My guess is that a given atheist in the USA is more likely to have read the entire Bible than a given Christian, but not more likely than a given fundamentalist Christian. That may explain my perception (if my perception is correct) that formerly Christian atheists are more likely to have been fundamentalist Christians than liberal Christians. Like me, I think they set out to read the Bible to deepen their faith, only to find it having the opposite effect.
As far as I know, there hasn't been a study on whether atheists in majority Christian countries are more likely to have read the Bible in its entirety than the Christians in their country. There was a Pew Survey on Religous Knowledge in the US that indicated atheists are more knowledgeable than any other group about religion in general (followed closely by Jews), but I think fundamentalist/evangelical Christians came out as most knowledgeable about their own religion.
My guess is that a given atheist in the USA is more likely to have read the entire Bible than a given Christian, but not more likely than a given fundamentalist Christian. That may explain my perception (if my perception is correct) that formerly Christian atheists are more likely to have been fundamentalist Christians than liberal Christians. Like me, I think they set out to read the Bible to deepen their faith, only to find it having the opposite effect.