File this under “Really Interesting Stuff Most Catholics Don’t Know.”

It doesn’t happen often, but every now and then a priest is unable to complete the holy sacrifice of the mass. What then?

Zenit, citing a theology manual from the 1930s, answers:

“Should a priest have to interrupt the Mass due to illness or another grave reason after he has consecrated either or both species — and is unlikely to be able to recover sufficiently within an hour — there is a grave obligation to have the celebration continued by another priest.

“In grave emergencies even a priest who has been excommunicated, suspended or otherwise irregular may finish the Mass.

“If the first priest is able to communicate he should be given communion from the species consecrated during the Mass.

“If no priest is immediately available, the hosts and the chalice (even if not yet consecrated) should be placed in the tabernacle until a priest can come to finish the Mass.

“The interval elapsing between the two parts may be of any duration but should be as soon as possible.

“If not-yet-consecrated wine were to spoil, or be certain to spoil, before a priest can come to consecrate it, then it may be poured down the sacrarium and replaced with new matter (wine and water) when the priest arrives.

“Only in very rare and extreme situations may the consecrated species of an interrupted Mass be consumed. Such occasions would be, for example, an imminent danger of profanation of the sacred species or the objective impossibility of safely keeping them, such as during wartime conditions or a climate where the species of wine would certainly become corrupt before a priest can come to complete the Mass.

“If the interruption were to occur before the consecration, with no priest to continue the celebration and no other Masses reasonably available, then a deacon, instituted acolyte or authorized extraordinary minister could distribute Communion from the tabernacle using the rite for Communion outside of Mass.

“If the interruption occurs after the priest’s communion, then the same ministers can administer the consecrated species to the faithful using the same rite.”

I find it fascinating that even an excommunicated priest, under some circumstances, can complete the mass.