OF THE RITE OF THIS SACRAMENT (SIX ARTICLES)
We have now to consider the Rite of this sacrament, under which head there are six points of inquiry:
(1) Whether Christ is sacrificed in the celebration of this mystery?
(2) Of the time of celebrating;
(3) Of the place and other matters relating to the equipment for this celebration;
(4) Of the words uttered in celebrating this mystery;
(5) Of the actions performed in celebrating this mystery.
(6) Of the defects which occur in the celebration of this sacrament.
Whether Christ is sacrificed in this sacrament?
Objection 1: It seems that Christ is not sacrificed in the celebration of this sacrament. For it is written ( Heb. 10:14 ) that "Christ by one oblation hath perfected for ever them that are sanctified." But that oblation was His oblation. Therefore Christ is not sacrificed in the celebration of this sacrament.
Objection 2: Further, Christ's sacrifice was made upon the cross, whereon "He delivered Himself for us, an oblation and a sacrifice to God for an odor of sweetness," as is said in Eph. 5:2. But Christ is not crucified in the celebration of this mystery. Therefore, neither is He sacrificed.
Objection 3: Further, as Augustine says (De Trin. iv), in Christ's sacrifice the priest and the victim are one and the same. But in the celebration of this sacrament the priest and the victim are not the same. Therefore, the celebration of this sacrament is not a sacrifice of Christ.
On the contrary, Augustine says in the Liber Sentent. Prosp. (cf. Ep. xcviii): "Christ was sacrificed once in Himself, and yet He is sacrificed daily in the Sacrament."
I answer that, The celebration of this sacrament is called a sacrifice for two reasons. First, because, as Augustine says (Ad Simplician. ii), "the images of things are called by the names of the things whereof they are the images; as when we look upon a picture or a fresco, we say, 'This is Cicero and that is Sallust.'" But, as was said above (Q[79], A[1]), the celebration of this sacrament is an image representing Christ's Passion, which is His true sacrifice. Accordingly the celebration of this sacrament is called Christ's sacrifice. Hence it is that Ambrose, in commenting on Heb. 10:1, says: "In Christ was offered up a sacrifice capable of giving eternal salvation; what then do we do? Do we not offer it up every day in memory of His death?" Secondly it is called a sacrifice, in respect of the effect of His Passion: because, to wit, by this sacrament, we are made partakers of the fruit of our Lord's Passion. Hence in one of the Sunday Secrets (Ninth Sunday after Pentecost) we say: "Whenever the commemoration of this sacrifice is celebrated, the work of our redemption is enacted." Consequently, according to the first reason, it is true to say that Christ was sacrificed, even in the figures of the Old Testament: hence it is stated in the Apocalypse (13:8): "Whose names are not written in the Book of Life of the Lamb, which was slain from the beginning of the world." But according to the second reason, it is proper to this sacrament for Christ to be sacrificed in its celebration.
Reply to Objection 1: As Ambrose says (commenting on Heb. 10:1 ), "there is but one victim," namely that which Christ offered, and which we offer, "and not many victims, because Christ was offered but once: and this latter sacrifice is the pattern of the former. For, just as what is offered everywhere is one body, and not many bodies, so also is it but one sacrifice."
Reply to Objection 2: As the celebration of this sacrament is an image representing Christ's Passion, so the altar is representative of the cross itself, upon which Christ was sacrificed in His proper species.
Reply to Objection 3: For the same reason (cf. Reply OBJ[2]) the priest also bears Christ's image, in Whose person and by Whose power he pronounces the words of consecration, as is evident from what was said above (Q[82], AA[1],3). And so, in a measure, the priest and victim are one and the same.
Whether the time for celebrating this mystery has been properly determined?
Objection 1: It seems that the time for celebrating this mystery has not been properly determined. For as was observed above (A[1]), this sacrament is representative of our Lord's Passion. But the commemoration of our Lord's Passion takes place in the Church once in the year: because Augustine says (Enarr. ii in Ps. 21 ): "Is not Christ slain as often as the Pasch is celebrated? Nevertheless, the anniversary remembrance represents what took place in by-gone days; and so it does not cause us to be stirred as if we saw our Lord hanging upon the cross." Therefore this sacrament ought to be celebrated but once a year.
Objection 2: Further, Christ's Passion is commemorated in the Church on the Friday before Easter, and not on Christmas Day. Consequently, since this sacrament is commemorative of our Lord's Passion, it seems unsuitable for this sacrament to be celebrated thrice on Christmas Day, and to be entirely omitted on Good Friday.
Objection 3: Further, in the celebration of this sacrament the Church ought to imitate Christ's institution. But it was in the evening that Christ consecrated this sacrament. Therefore it seems that this sacrament ought to be celebrated at that time of day.
Objection 4: Further, as is set down in the Decretals (De Consecr., dist. i), Pope Leo I wrote to Dioscorus, Bishop of Alexandria, that "it is permissible to celebrate mass in the first part of the day." But the day begins at midnight, as was said above (Q[80], A[8], ad 5). Therefore it seems that after midnight it is lawful to celebrate.
Objection 5: Further, in one of the Sunday Secrets (Ninth Sunday after Pentecost) we say: "Grant us, Lord, we beseech Thee, to frequent these mysteries." But there will be greater frequency if the priest celebrates several times a day. Therefore it seems that the priest ought not to be hindered from celebrating several times daily.
On the contrary is the custom which the Church observes according to the statutes of the Canons.
I answer that, As stated above (A[1]), in the celebration of this mystery, we must take into consideration the representation of our Lord's Passion, and the participation of its fruits; and the time suitable for the celebration of this mystery ought to be determined by each of these considerations. Now since, owing to our daily defects, we stand in daily need of the fruits of our Lord's Passion, this sacrament is offered regularly every day in the Church. Hence our Lord teaches us to pray ( Lk. 11:3 ): "Give us this day our daily bread": in explanation of which words Augustine says (De Verb. Dom. xxviii): "If it be a daily bread, why do you take it once a year, as the Greeks have the custom in the east? Receive it daily that it may benefit you every day."