Yesterday, I posted a Catholic Dilemma that was published a while ago in the Catholic Herald on The priest, sin and saying Mass. In these articles I have to keep within 350-360 words and therefore there are always things that I have to omit. (This is a very salutary discipline for a writer, I think: it certainly helps you to be ruthless with redundant words and phrases - as you might very much say, so to speak, if I might be somewhat rather a bit bold...)
In this case, however, there is a particular point that is worth following up (and will be the subject of a future Catholic Dilemma.) If the priest is bad, does that affect the validity of the Mass or of the sacrament that he ministers? People do often get confused on this matter.
The Donatists of the 4th and 5th centuries held that those who had handed over the scriptures as a token of repudiating the faith under persection - the traditores - could not adminster baptism validly. They maintained that people had to be baptised by one who was part of the Church of the saints.
St Augustine opposed this heresy and clarified for posterity the important principle (implicitly part of the apostolic tradition) that the sacraments do not depend on the worthiness of the minister because the sacraments are primarily works of Christ. His most famous words on the subject are:
Peter may baptise, but this is He [Christ] that baptises; Paul may baptise, yet this is He that baptises; Judas may baptise, still this is He that baptises. (In Evangelium Ioannis Tractatus. 6.7)So even a bad priest can offer Mass validly, baptise validly, give valid absolution, and so on for the other sacraments.
There are plenty of other matters related to the validity and fruitfulness of the sacraments (valid matter and form, intention to do what the Church does, impact on the devotion of the participants...) but there are shallows and rocks in all of them it is probably best to stick to one question at a time.
This summer I hope to make some progress on getting my notes for Sacramental Theology into publishable form.