1st Com. made by Antiphon and Versicle of Lauds. 2nd Com. made by Antiphon of second Vesper and Ver. of II. Nocturn. 3rd Com. made by Antiphon of I. Noct. and Vers. of III. Nocturn.
IN LAUDS—
1st Com. made by Antiphon and Vers. from first Vesp. 2nd Com. made by Antiphon I. Noct., and Ver., III. Noct. 3rd Com. made by Antiphon II. Vesp., Vers., II. Noct.
If it should happen in commemorating a day within an octave that the versicle from the common had already been taken for the office, then the rule is "Sumenda est in laudibus antiphona de secundis Vesperis; et pro secundis Vesperis antiphona de laudibus in utroque tamen casu cum v. de primis Vesperis" (S.C.R., 18th Dec., 1779). In the above given form of making commemorations it may be noted that the second commemoration in Lauds is made up from the versicles and response of Matins and not from second Vespers, so as to avoid repeating in Lauds what was said at Vespers (Cavalieri).
As regards prayers in the office the reminder that the same formula must not be repeated in the same hour may be supplemented. Because, prayers having all words identical, save one single word, are not considered in liturgy as different prayers (e.g., Accendamur exemplis; instruamur exemplis, Feast of St. Philip and St. James, Feasts of several martyrs). So, too, prayers which have the same form of petition (e.g., the prayers on feast of St. Joseph and on feast of St. Mathew), are not considered as different and must not be repeated in the same hour. But where the petition is different, even though all the remainder of the prayers are similar in wording, they may be repeated in the same hour.
But what is to be done in offices where a commemoration prayer and the prayer of the office is from the common? What must be done where the feast is the feast of a Doctor and a commemoration of a Doctor is to be made? What is to be done when the office of the feast is of a virgin not a martyr, and a commemoration of a virgin not a martyr is to be made? In the first case the prayer from the office of a confessor or Pontiff should be said, adding to it the title of Doctor. In the other case, the prayer Indulgentiam, omitting the word martyr, is to be said.
The origin of these commemorations was, that the Popes in removing the solemn celebrations of certain feasts of Apostles and Martyrs, which were formerly of precept, provided that their cultus should not be forgotten, and that their commemoration in the office should remind priests and the faithful of those servants of God, whom the Church wishes ever to honour. I have said the order given for commemoration in the Ordo should be followed; but not to follow this order does not exceed a venial sin. Even the deliberate omission of a commemoration in Lauds or Vespers is not a violation of a grave precept.
TITLE X.—THE TRANSLATION OF FEASTS.
When several offices fall on the same day, only one office, the one of highest rank or most important, is said. The others are transferred or commemorated. The last section dealt with commemorations, and now we come to the difficult question of the translation of feasts. Title X. of the general rubrics must be read in connection with the Apostolic Constitution, Divino Afflatu (1911) and with the Abhinc duos Annos (1913).
Translation of a feast may mean the removal of a feast from an impeded day to a day which is free. Thus a feast of higher rank may fall on a feast day of a saint whose feast is of lower rank; the latter may then be transferred. Transference is either perpetual or accidental and temporary. The former applies to feasts which are always impeded by the meeting with a feast of higher rite on their fixed days. A feast which would fall on 6th January would suffer perpetual translation. This translation bears different names in rubrics, decrees and liturgical writings—translatio ad diem, fixam, translatio ad diem assignatam, mutatio, etc. Accidental translation means occasional transference, a transfer in one year and not in another.