Under another entry, frequent contributor Henry brings up a very good question.
To begin here are a couple comments, or rather "hooks" to hang ideas on.
First, a bishop can establish a "personal parish" where only the older, pre-Conciliar liturgical forms are used. In such a place the 1962 Missale Romanum would be used for the Triduum, not the Novus Ordo.
Second, we have all heard about the tea-pot tempest surrounding the Good Friday prayer for Jews in the older form. Surely some bishops would have hesitated to establish personal parishes because those controversial prayers would have then been actually used, thus stirring controversy. Then Pope Benedict changed those prayers for Jews. In doing so the Pope a) removed a possible objection to establishing a place where the older form would be used on the Triduum, and b) gave a clear sign that he intended that the Triduum be observed also with the 1962 form! Remember: he could have ignored it. By giving it this attention, he shows his favor.
Third, no priest or bishop can now say that, because of the prayers for the Jews on Good Friday, he doesn’t want people to use the 1962 Triduum. That would be a criticism of Pope Benedict’s shiny new prayers, which would be seriously inappropriate. A bishop or priest could come up with some other obstacles, but that one is now off the table.
So, with those ideas in place, take a look at what our friend Henry posted:
Henry: But suppose the pastor of a parish that regularly celebrates only the ordinary form accepts a liturgy committee recommendation that for a special occasion a particular Triduum Mass be celebrated in the extraordinary form instead. I recall a pastor who during the pre-SP speculation indicated his intent to do just this—celebrate the Christmas and Easter Vigil Masses in Tridentine form. Is there anything in SP that prohibits this?
Fr. Z’s short answer: No.
Keep in mind we are considering a parish where the Novus Ordo is the usual form used.
Here is my translation of article 2 of the Motu Proprio:
Art. 2. In Masses celebrated without the people, any priest whosoever of the Latin Rite, whether secular of religious, can use either the Missale Romanum issued in 1962 by Bl. John XXIII, or the Missale Romanum promulgated in 1970 by the Supreme Pontiff Paul VI, and indeed on any day whatsoever except during the Sacred Triduum. For such a celebration according to one or the other Missal, a priest does not need permission, neither from the Apostolic See nor from his Ordinary.
This is the only place in the Motu Proprio which mentions the Triduum. This article concerns private celebration of Mass.
Background: During the Triduum there cannot be a multiplication of Triduum ceremonies in the same place. You cannot have Novus Ordo Holy Thursday at 7:30 and 1962 at 9:30. Nor can a priest celebrate these things privately, or do one in private and one in public. A priest may not celebrate any Triduum rite privately with either Missal.
I do not find anything in Summorum Pontificum which would prevent a parish where the Novus Ordo is the usual form from having the Triduum in the older form.
Let’s go on.
In article 5 § 2 we read:
Celebration according to the Missal of Bl. John XXIII can take place on weekdays; on Sunday, however, and feasts there can be also one celebration of this kind.
The Motu Proprio mentions Sundays, weekdays and feasts. Are we to understand "feast" in a broader sense? Are we to understand that these terms apply to the older calendar, as found in the 1962 Missale Romanum or according to the newer, post-Conciliar calendar. The new calendar distinguishes between solemnities, feasts, and memorials. So, if we are to take it that the Motu Proprio is referring to these days when the old Mass can be used publicly it seems like we might not be able to use it on solemnities or the Triduum (which outranks all other solemnities). However, I don’t think we have to assume that the Motu Proprio is speaking of the newer calendar at all. Article 5 § 2 is talking about only one Missal and it mentions only the older Missal. The older Missal does not distinguish solemnities, and neither does this article. I think the article is intended to be read from the point of view of the older structure of the calendar rather than the newer, post-Conciliar distinctions. So, given that the older form of Mass can be used on ferial days, Sundays and feasts, that covers every day of the year, I think. After all, is not Good Friday considered a ferial day in Holy Week? I don’t have an old Ordo with me but I think so.
So the Motu Proprio says, I believe, that there can be a celebration with the older form on any day of the year. However, there can only be one ceremony on each day of the Triduum in any given place. Therefore, it must be either the Novus Ordo or the 1962 form.
The Motu Proprio suggests to me that a pastor could choose the older form instead of the newer form. Furthermore, he does not need permission from the bishop.
I do not know if this is clarified in the upcoming document from the Pope.
Remember: Pope Benedict intends that the older form can also be used on Good Friday. If he didn’t, he would have ignored the Good Friday issue. By changing the prayer he intends that it can be used also on Good Friday. That doesn’t mean that it must be used, only that it can be used. If I understand Benedict’s way of thinking, he would be very disappointed with a pasto