So, what makes the Atheist version more compelling? Is it that the Atheist, who is well loathed in lore-americana, gets his one uppance for being so forthright? Or for muttering the words "oh god", instead of saying "oh shit", or "I'm, fucked".
Well, we all know that time cannot stand still, that a presumed sky god cannot actually talk to someone, that a bear has never spoken, lacks the physical ability in fact to do so, has never spoken let alone become christian. These things cannot happen and we all know that they cannot happen.
But they'd be funny if they did... at least to us, the on lookers, not to the Atheist.
So basically, it's saying that, true, all that, but fuck that Atheist anyway for pointing out the obvious. And Ha Ha. At least that's how I read it, and that's what possibly makes it funny.