Curiosity would have sufficed as an answer, but as Rezo expounds, Donnie nods thoughtfully.

"And maybe even find similarities?" Finding familiar things is comforting in its own way when you were so far away from home. "...what does a priest do?" He has zero experience with priests, and from what he's learned about Rezo, the man doesn't seem all that different from other people, although his command of magic is intriguing.