If it were me, since I would only be a visitor, I would say that I give of my time and talents to my church. But, I don't know the exact nature of the help he's asking. How often do you visit? Is the asking making you uncomfortable and not wish to visit again? I don't know all of the facts, but if the priest is asking a visitor for assistance with something in the church (Would you elaborate in what form the help is to take?) then that indicates to me there is something very wrong with either the relationship between the priests and the parishioners or the parishioners are just unwilling to care for their parish or some combination of the two. I don't want to go the pessimistic route, but I've never been contacted by a priest in the city I live in to help out there even if I do visit on occasion.