I have never understood the metaphor argument. When I was a believer I believed it all literally. If this stuff is a metaphor then what it is a metaphor for? Also if it is a metaphor how come (especially in the prophets) the Bible spends so much time listing metaphors and then explaining them? How come when the Bible self-references it treats itself literally?

Adam and Eve were the literal truth to Paul and he used it to create his theology of original sin.