Today is Saturday in the first week of Advent. The day is of simple rite and as such its Mattins consist of one nocturn and three lessons.
The Breviary needs to be marked in two or three places for Mattins: Sabbato ad Matutinum, Saturday of the first week in Advent for the lessons and the Ordinarium depending on the layout of the particular edition being used.
Mattins begins with the prayer Aperi Domine followed by the inaudible recitation of Pater noster, Ave Maria and Credo. Then the versicle Domine, labia mea aperies (with the Sign of the Cross made on the lips) and its response Et os meum annuntiabit laudem tuam. Turning now to the section Sabbato ad Matutinum the invitatories for Advent are given. For the first and second weeks this is Regem venturum Dominum * Venite adoremus. This is said in its entirety, then repeated and followed by the first part of Ps. 94 Venite, exsultemus Domino etc found in Ordinarium. The invitatory is then, again, repeated in its entirety. The next section of the psalm is then said Quoniam Deus magnus etc. After that the fragment of the invitatory, Venite adoremus, only. Then the next part of the psalm Quoniam ipse est mare etc followed by the entire invitatory. Next Hodie si vocem etc followed by the fragment, then Quadraginta annis followed by the entire invitatory. Then the Lesser Doxology, fragment of the invitatory and, finally, the entire invitatory is said again.
The hymn Verbum supernum prodiens is then said.
Now the nocturn is said. The first antiphon given for Sabbato ad Matutinum, Memor fuit, is said only as far as the asterisk, i.e. Memor fuit in saeculum. This is because today is not of double rank. Then the first psalm, Ps 104(i) Confitemini Domino is said. Then the lesser Doxology and the antiphon in its entirety is repeated, Memor fuit in saeculum testamenti sui Dominus, Deus noster. Then the second antiphon as far as the asterisk, the second psalm, Lesser Doxology and the antiphon in its entirety. This arrangement is repeated for the third psalms and its antiphon.
After the repitition of the third antiphon unlike in Mattins of nine lessons the versicle and response etc is NOT said here. Instead the antiphon fragment of the fourth psalm, Salvavit eos Dominus is said. Then follows the fifth antiphon and psalm followed by the sixth. After the repitition of the sixth psalm again the versicle and response etc are not said but the fragment of the seventh antiphon. Then the seventh psalm etc, the eighth and ninth. After the repitition of the ninth antiphon, Videbunt recti etc then an antiphon and versicle are said. The antiphon is that for the ferial office of Advent Egredietur Dominus and its response Veniet. Then is said the Pater noster, inaudibly, followed by the versicle Et ne nos inducas in tentationem and the response Sed libera nos a malo.
Then is said the absolution A vinculis etc followed by Jube, domne and the first blessing Ille nos benedicat. (The blessings vary according to whether Mattins has three or nine lessons, whether it is a feast of the BVM or Saint, and whether a Gospel fragment is read or not. Which blessing is said when is easily learnt with practice). Then turning to Saturday of the first week of Advent the first lesson is Et factum est in diebus Achaz etc followed by its responsory Ecce virgo concipiet. After the responsory again Jube, domne and the second blessing Divinum auxillium etc. Then the second lesson is said Et dices ad eum followed by its responsory Audite verbum. Then again Jube domne and the third blessing Ad societatem etc and the third lesson Et adjecit Dominus etc. Unlike on a feast, or in Paschaltide, at ferial Mattins the Te Deum is not said. In its place a third (or ninth) responsory follows. For today this is Ecce dies veniunt.
After the third responsory Lauds follow. (In private recitation, if Lauds are not said, the ending of Mattins is as given in the first example here with the collect of the first Sunday of Advent being used.)