That would very much depend of the god. If their god is a god of law and good behaviour they'd be expected to uphold his codes. If he's a trickster deity they'll probably have a lot more freedom but heaven help them if they don't have a sense of humour. Some priests will have a complex set of taboos to do with their deities preferences other will have it more relaxed. And so on...
And the gods do answer other people's prayers - it's just they always (or almost always) answer their priests' prayers. It's kind of like a divine contract - the priests make sure the gods get fed (worshipped) and the gods answer the priests' prayers.
Religion and magic are so intertwined on Nertha that this will all probably make more sense when I cover religion and how the titans/gods/outsiders thing actually works. At the moment this only part of the picture.
So are you enjoying reading these little essays so far?