"Oh!" Aziraphale isn't offended so much as incredibly surprised to hear that a world exists with no gods. Not even god with a capital G, whose presence he takes for granted, even in the Nexus. "Well, that's... goodness. Hmm. And he's certain about that?"

It's one thing to be an atheist. Humans can get by perfectly well without religion or a belief in the spiritual. But the same isn't true for an angel. In a world without God, where would that leave him? Maybe he should rethink that vacation to Alpha Centauri...

Crowley's joke earns a weak smile from Aziraphale, who is actively trying to shake off his bout of existential awkwardness. "'Vintage' is not a word you ought to apply to stew, Crowley. I'm sure it's been made fresh. Certainly, we can try things in that order."