I didn't play a priest then. If priests are nobles, then they are in the feudal system. If you kick them out, then they're commoners.
Not really. Remember the whole "three classes" stuff? Nobles, the clergy, and the serfs? The church was apart of the feudal hierarchy because they responded to god, and so forth, hence why church properties were not taxed.
I still prefer priests being in the feudal system, though, it's more fun.