The Church lives in a time unsettled by the ultra vires actions of that rascal Bartholomew of Constantinople and by the Russian incursion into Ukraine. Recently, a former Catholic seminarian has converted to Orthodoxy and has some specific questions about the validity of the sacraments performed by a priest who finds himself a member of a local Church which has fallen into schism for various reasons. This was my response to this convert:
“Please allow me to toss in my two cents as a former Anglican priest who used to consider his ordination to be valid by virtue of the Branch Theory. I have put that behind me and am now a lay convert to Orthodoxy like you.
“I would like to say two things: 1. The Western approach to the sacraments is based on the validity conferred on the priest via the Apostolic Succession, as is the Eastern approach. Without the ministrations of a validly ordained priest, there are no efficacious sacraments.
“However, we must remind ourselves that the Western approach is highly rationalistic and legalistic, whereas the Eastern approach is mystical and holistic. In the West, proof of a cleric’s spot on the apostolic genealogy is the ticket to his ability to celebrate valid sacraments. In other words, if the bishop who ordained you was properly consecrated, then your ordination is valid forever, no matter what. That is true in the East, as well, but the East demands one further criterion for validity, i.e., obedience to the Apostolic Tradition in addition to Apostolic Succession.
“As the others have suggested, a priest’s ordination may be valid, but if he is not in right relationship with his bishop, or if a bishop is not in right relationship with his synod or fellow bishops of other local (read: national) churches, the Eucharist that he confects and the other mysteries (read: sacraments) that he serves (read: celebrates or officiates) are called into doubt, or are rendered graceless outright. That is, for all intents and purposes, they are null and void. Whatever grace that the communicants at his liturgies may receive regardless of this fact are, one must suppose, due to their personal faith, but not due to the objective invalidity of the mystery itself (read: sacrament).
“Having said all that, I’ll posit my second point: 2. Unless you put out of your mind the highly rationalistic mentality of the Thomist West, you will not be able to “loosen your belt”, shall we say, and open your heart to understand the mind of the East. God will impute his grace upon those whom he will impute it, regardless of the strict adherence to the rules of valid ordination, regular elements, set form, and right intention.

“Elder Arsenie of Paparocioc, a Romanian monk priest who was persecuted terribly during the 20th century is one example. When Fr. Arsenie was imprisoned, he would take water and a morsel of bread and celebrate the Eucharist for himself and his fellow captives. He admitted that he didn’t know if it was “the real thing”, but he did what he could in his circumstances to pray to God and to administer God’s grace in the hope that it was effectual unto salvation for the poor souls. Certainly his actions were taken in extremis and God only knows if there was any validity to them, but it seemed to strengthen his faith and that of his comrades. Of course, the exception does not disprove the rule, but I hope you’ll get my point.
“All that I am trying to say, however feebly, is that we who have been tutored in the rationalistic Western tradition have a good deal of “unlearning” to do before our Eastern catechism can settle in and take root. God works primarily inside the box, but he certainly is not confined by the dimensions of the box and is free to work outside of it.
“On the other hand, those clerics who consider themselves to have obtained some grace that they are free to dispense and manipulate without the strictures imposed upon them by the discipline of the Church are sadly mistaken, for the grace is not theirs to clutch, but rather is bequeathed upon them by the Church for the sake of the building up of the Church according to the Church’s discipline. He who would be first within the Church must become the servant of all.
“I don’t know if that helps, but there it is for what it’s worth.”