On the substance of that portion of the discussion, I don't see why it would be so strange to have an unbeliever ask a believer to take a deeper look at scripture. Why wouldn't we? It's from a deeper look at scripture that we realize the evolution of Yahweh as a character (we would add "fictional" to character, but that would be presumptuous). It's from a deeper look at scripture that you realize the cosmology of Genesis is incompatible with what we know to be true. There is no firmament (big solid wall) holding back water from the sky.
I personally WELCOME in depth analyses of scripture. What I don't accept is ad hoc explanations that force scripture to say things it doesn't say. The firmament is not "the expanse" or "the universe." The Exodus from Egypt was not a secret prediction that Jesus would spend a couple of years as a baby in Egypt. The "virgin shall conceive and be with child" has nothing to do with the messiah. When you take a deeper look at the verses that are supposedly fulfilments of old testament prophecies, you will find more often than not that the prophecies are not talking about the messiah at all.
Oh but they're types. Nope, that's made up.