Priests should dress tastefully and modestly, just as we all should, whether they are “on” or “off” duty. But, except for members of some religious orders that wear habits, they don’t have to follow any specific dress code. Black clothes and the Roman collar are extremely common for parish priests in the United States but are certainly not required. Depending on the community in which a priest is serving, he may never wear them or may wear them only on special occasions. Some priests may choose to dress in black and wear a Roman collar when they are at work, and then to wear different clothes when they are out of the office or away from the parish, as a sign to others (and to themselves) that they are taking a day of rest. Others may prefer to wear the Roman collar even on their days off. (Keeping to the uniform certainly makes shopping for clothes easier!) But, in general, priests should dress in a dignified manner that respects the culture and the community in which they minister.