Well, there we'd get into the whole question of how much D&D's whole divine/arcane magic split even makes sense. I mean, if people legitimately can do magic without needing any help from the gods at all, that makes magic just another "mundane" part of the world -- and then what does that in turn make the gods other than perhaps just another sort of powerful wizards? How would you be able to tell the difference?But in a world that also has fireball casting wizards that part wouldn't be especially important relative to belief, would it? The power of the god wouldn't be in the magic, because lots of people could do magic, but in the spiritual aspects. Those would still be true for people.