I have already at length discoursed upon that liturgical curiosity, the triple Mass, when discussing the Missa trifaciata offered at Christmas in the Dormitionist Order; for lesser but still prominent feasts, those Canons maintain the antique custom of offering up a twofold Mass, a Missa bifaciata.
Passion Friday, as all men know, is the last Lenten Friday before Good Friday; while in past centuries, throughout the worldwide Church, on this day both a ferial Mass of Lent and a festal Mass of Our Lady of Sorrows would normally be celebrated, the Canons of Our Lady’s Dormition unite these two observances into one. Having begun Mass with the usual prayers, the Mass Stabant juxta Crucem is begun, and continued down to the end of its Offertory Recordare Virgo Mater; then comes the famed liturgical stutter so named by the learnèd Pickstock – the Introit of the ferial Mass, Miserere mihi Domine, is read, and so the rest of that formulary down to its Offertory, Benedictus es Domine. Only then, after this twofold Mass of the Catechumens (first one for devout children of Mary Sorrowing, the other for clients of Santa Feria), is the one Mass of the Faithful begun. The details of this need not detain us, further than to note that a Secret is read from each formulary, and likewise two Communions and two Postcommunions are read, followed by the Lenten Oratio super populum peculiar to the feria. The Preface, of course, is that of the Holy Cross, ’neath which the Dolorous Virgin took her stand.
Similarly, at the Greater and Lesser Litanies, Missæ bifaciatæ are celebrated – that is, on St Mark’s day (Mass of the Apostle, united with the Mass of Rogation), and, if saint’s feasts occur, on each of the days of Rogationtide. Moreover, if a saint’s day fall on Rogation Wednesday, Ascension Eve, a Missa trifaciata is celebrated: thrice the Mass of Catechumens is prayed, once for the saint, once for the Vigil of the Ascension, and once for the Rogation. (While according to the Roman Missal those three Masses would, even down to the 1950's in collegiate churches, have been said after Terce, Sext and None respectively on Rogation Wednesday, the Dormitionist practice of saying all three by aggregation before Compline is plus simple et plus uni.)
Again, ancient Missals of the Roman Church contain multiple Masses for the feasts of St John the Baptist and of St Lawrence: as well as the day Mass of each, there was a matutinal or early morning Mass. The Dormitionists have conserved the texts of both of these, but unite them with the Mass of the respective day as two more Missæ bifaciatæ. (After all, how could these religious, devoted as they are to even now pursuing a foretaste of eternal rest, celebrate early morning Masses when their Rule obliges them to evening Masses only?)
As with Christmas, so with Maundy Thursday: just as the Holy Roman Church of old time celebrated three Masses on that day – for the Reconcilation of Penitents, for the Consecration of Chrism, and of the Lord’s Supper (in Cæna Domini) – so the Dormitionists unite all three formularies into one (though of course no chrism is blessed, nor penitents reconciled for that matter). There is no procession afterward, nor use of an altar of repose (just as the Carthusians refrain from such*); rather, the priest having consecrated a second Host, It is reserved in the usual manner and, Mass ended, the Discourse of Our Lord is read (St John, chapters xiii to xvii) as a most fit introduction to Compline, which follows directly.
* In a similar way (excuse this strange expression), the Dormitionists and Carthusians imitate each other in simply and soberly celebrating Ash Wednesday, Palm Sunday and Candlemas: for on none of these days is there any procession held in either Order; rather, the ashes, palms and candles respectively are blessed with a suitable prayer and distributed, whereupon Mass begins at once. The Dormitionists have but one variant ceremony: for more expedition, the ashes and palms respectively are immediately thrown over the prostrate brethren, themselves resembling mere scattered ashes and bestrewn palms (as those humble religious delight to confess). The candles, however, are not distributed until after Mass, for they are too large to throw without danger – since it is intended that the brethren carry them as night-lights back to their cells after Compline, and it would be ridiculous and unseemly to carry broken candles, especially if injured by them. (The two Orders also diverge in their observance of Corpus Christi; while Carthusians hold a Eucharistic procession, Dormitionists – imitating Belgian practices, and what I remember of that feast at the Pro-Cathedral in Perth, W.A. – content themselves with celebrating Mass and Compline of that feast coram Sanctissimo, the Host exposed in a monstrance above the High Altar throughout.)
How odd, I reflect, it is, that dear Archdale Arthur King, in his Liturgies of the Religious Orders (which I have in facsimile before me) wasted paper on an account of the extinct Gilbertines and their fragmentary remains, and so for want of space neglected to give any decent account of the still-extant and far more intriguing liturgies of the Dormitionists! At least in my own online musings I have almost covered all the topics he discussed when explicitating the practices of the Carthusians, Cistercians, Premonstratensians, Carmelites, Dominicans, and those unfortunate Gilbertines. Deo gratias.