Priests will be like priests, and do priestly stuff. Which is to say that they preach and proselytize. Monks, meanwhile, will be like monks and do monkly stuff. Which is to say that they will hide out in monasteries and be all educated and scribely and stuff.

Neither will resemble their D&D namesake, which oddly enough resembled nothing of which either of those professions did in history. Which is fine, I guess, if oddly misleading (like confusing a whole generation of players as to the true nature of the morningstar and the medusa/gorgon).

Oh, and they'll mostly be women. But that's this whole other thing.