Proof that God doesn't exist

[Edwardo Piet]

That basically brings us back to square one; what is this Original Sin that Jesus is saving us from?

Well, if it's purely allegorical we don't have to know what it is, you still haven't proved that it doesn't exist. If it's allegorical then, it could refer to a number of logically possible things.

Works in mysterious ways that are synonomous to his non-existence.

Works in mysterious ways that are indistinguishable to his non-existence, rather. It's not synonymous because it isn't a similar meaning - a "God that works in mysterious ways" is still a God. It has a completely different meaning because it still implies that there was at least a "God" that created the universe and some other parts may be literal such as Jesus being himself incarnate. You can't disprove those parts if the rest is allegory. We can't tell the difference - but that's the whole point of the Christian God anyway - he's completely undetectable. He's invisible, intangible, etc, so how have you proved that he doesn't exist if the only literal parts are that God created the universe and Jesus is himself incarnate?

That apologetic line is evasive and a cop out.

I agree that there are many cop-outs, but that just proves that there's no evidence for God, it doesn't prove that he doesn't exist if the interpretation of his existence is the almost entirely allegorical case I described above.

Sure, the "sloppiness" is subjective, but it nontheless shows God isn't all-powerful and couldn't will his word how he wanted to.

You haven't demonstrated that he isn't "all powerful" if he merely "works in mysterious ways".