Viking Bastard
Adventurer
In godless settings, I apply a similar concept. The energy that is behind all magic is an alignment neutral magic-stuff. How it forms in reality depends on how it is channeled. In the case of "divine" (good and evil) it is the will of the user that defines what sort of form is takes. "Gods" are the will of the faithful shaping the magical reality of the universe. They're as strong and as capable as their followers are numerous and faith is strong but they aren't "real". Some "gods" have metagame this system in order to perpetuate their "existence". There's some neat tricks to this system which are somewhat existential and difficult to explain in a text post.
I have always kind of taken this to be the D&D default, on the one hand because my introduction to the game through the "god neutral" BECMI/RC and on the other hand because of my early introduction to Planescape, which I immediately interpreted this way. Gods exist because we believe them to exist, so all gods are motivated to spread their message because otherwise they would stop existing. Sometimes gods will create worlds and populate them with people, to basically serve as a power generator for their continued existence.
The Outer Planes as a whole are what we believe them to be, but they have always been as we believe them to be and they always will be--except we used to believe they were different, and back then they had always been like that and were always going to be like that. In the future, our ideas will have changed and so will the Outer Planes--their present, their past, and their future.
Or such. Wibbly-wobbly.