Were they all vessels of God?

They were called avatars. By definition an avatar is "a manifestation of a deity or released soul in bodily form on earth; an incarnate divine teacher." So I always thought they were people God created for himself to use to appear to Joan. This would apply to people like Old Lady God who appeared in many different situations. But in some cases, that idea doesn't fit. So I'm inclined to think now that they were people that God temporarily borrowed in order to appear to Joan. Mainly because of characters like the gay office admin at the school. If he was really the school admin, then it seems God only became him when necessary. And what about Johnny Broadway/Godway? That avatar broke all the rules.

I think the bottom line is there's no hard and fast rule. He's God. He can do whatever He wants or needs to in order to reach Joan. So maybe it's a little of both.

To me, the most interesting aspect was always the fact that Adam was the only one of the other main characters we see interacting with any of the Gods. He got jealous of Joan dancing with Cute Boy God. He asked who Goth God was when he saw Joan talking to him. He literally bumped right smack-into Office Admin God. And look at the whole thing with Johnny Godway. I always thought they were building toward something with that. And then the whole thing with Adam getting close to Ryan after breaking up with Joan happened. I thought that probably one of Joan's struggles for Season Three would have been her fighting against Ryan's corrupting influence on Adam, a literal fight for Adam's very soul.
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