Q. Recently I visited my home parish in Ohio (Diocese of Toledo). I was there to attend the 8:30 a.m. Mass on Dec. 24. Before Mass, the regular priest announced that there would be a substitute priest for that Mass because of the limit of "three Masses a day." (The regular priest was scheduled to do a different Mass that morning and then two Christmas Eve Masses later in the day.)

My question is this: Is this "three-Mass rule" a strict law of the church or a guideline? (I had never heard of it before.) If it's a law, could it be overturned in an emergency? For example, say a large parish with two priests had one get sick and no substitute could be found: Would a Mass (or two) have to be canceled? (Williamsburg, Va.)

A. It may come as a surprise for some Catholics to learn that there is any limitation at all on the frequency with which a priest may celebrate Mass. The truth, however, is that for centuries the church has regulated that number — primarily, to ensure that the Eucharist is celebrated with the dignity and devotion it deserves.

The current Code of Canon Law says that "if there is a shortage of priests, the local ordinary can allow priests to celebrate twice a day for a just cause, or if pastoral necessity requires it, even three times on Sundays and holy days of obligation" (No. 905.2).

In many dioceses, bishops have given their priests blanket permission to invoke this "twice on weekdays, three times on Sunday" option. The date to which you refer — Dec. 24, 2017 — was a Sunday, and so your local pastor was not "making up" a rule; the three-Mass limit was in place.

Interestingly — for many Catholics do not know this — a priest is not strictly required to celebrate Mass every day. Canon 904 says simply that "priests are to celebrate frequently" — although the same canon goes on to say that "daily celebration is recommended earnestly."

For genuine pastoral emergencies, a bishop is empowered to grant a dispensation even beyond the "three-Mass limit" — such as the situation you raise where a sudden sickness and lack of a substitute might compromise the need of the faithful for the Eucharist. 

Questions may be sent to Father Kenneth Doyle at askfatherdoyle@gmail.com and 30 Columbia Circle Dr., Albany, New York 12203.