Your argument, then, is not with the Bible or Christianity, but with mainstream Christians. No wonder you can't find the logic.And I'm not biblical scholar so I won't be able to put anything within biblical contexts to any degree of satisfaction.
The bible is just a collection of stories as far as I'm concerned.
They are great enduring morality tales adapted from the myths of the surrounding civilizations around them and before them, but they aren't history or science.