I'm gonna point out that there are certain paladin lines that do seem to imply worship of a god, it's even almost stated to be Tyr during the whole Anders quest. So that just makes me think there's more there that we haven't seen, one way or another.

Another thing that's just occurred to me. People are throwing out the term atheist paladin and I don't think that automatically reflects the state of our character. I think something that gets lost in these games is that the assumption is every character believes in the gods, and has one god they revere in particular above the others. So it only goes that any paladins we make would be the same. It's not that they don't believe in any gods, it's just that the gods aren't the chief guiding compass they serve, that would be their oath. And I think if we keep that in mind then it makes the idea of paladins who don't take their oath directly to a god make a bit more sense. Since any paladin will probably still have a patron god who is in line with their oath. So I can see it as a situation where the paladin makes the oath in a way that's not tied to a specific deity, but they still have their deity they pray to and revere, and that deity notices them because of this oath they took, an oath which exemplifies their divine virtues even if they don't directly act in service to the god. So the god grants them power in acknowledgement of their devotion.