So then, after the people have been prepared and instructed, the next step is to proceed to the celebration of the mystery, which is both offered as a sacrifice, and consecrated and received as a sacrament: since first we have the oblation; then the consecration of the matter offered; and thirdly, its reception.
In regard to the oblation, two things are done, namely, the people's praise in singing the "offertory," expressing the joy of the offerers, and the priest's prayer asking for the people's oblation to be made acceptable to God. Hence David said ( 1 Para 29:17 ): "In the simplicity of my heart, I have . . . offered all these things: and I have seen with great joy Thy people which are here present, offer Thee their offerings": and then he makes the following prayer: "O Lord God . . . keep . . . this will."
Then, regarding the consecration, performed by supernatural power, the people are first of all excited to devotion in the "Preface," hence they are admonished "to lift up their hearts to the Lord," and therefore when the "Preface" is ended the people devoutly praise Christ's Godhead, saying with the angels: "Holy, Holy, Holy"; and His humanity, saying with the children: "Blessed is he that cometh." In the next place the priest makes a "commemoration," first of those for whom this sacrifice is offered, namely, for the whole Church, and "for those set in high places" ( 1 Tim. 2:2 ), and, in a special manner, of them "who offer, or for whom the mass is offered." Secondly, he commemorates the saints, invoking their patronage for those mentioned above, when he says: "Communicating with, and honoring the memory," etc. Thirdly, he concludes the petition when he says: "Wherefore that this oblation," etc., in order that the oblation may be salutary to them for whom it is offered.
Then he comes to the consecration itself. Here he asks first of all for the effect of the consecration, when he says: "Which oblation do Thou, O God," etc. Secondly, he performs the consecration using our Saviour's words, when he says: "Who the day before," etc. Thirdly, he makes excuse for his presumption in obeying Christ's command, saying: "Wherefore, calling to mind," etc. Fourthly, he asks that the sacrifice accomplished may find favor with God, when he says: "Look down upon them with a propitious," etc. Fifthly, he begs for the effect of this sacrifice and sacrament, first for the partakers, saying: "We humbly beseech Thee"; then for the dead, who can no longer receive it, saying: "Be mindful also, O Lord," etc.; thirdly, for the priests themselves who offer, saying: "And to us sinners," etc.
Then follows the act of receiving the sacrament. First of all, the people are prepared for Communion; first, by the common prayer of the congregation, which is the Lord's Prayer, in which we ask for our daily bread to be given us; and also by private prayer, which the priest puts up specially for the people, when he says: "Deliver us, we beseech Thee, O Lord," etc. Secondly, the people are prepared by the "Pax" which is given with the words, "Lamb of God," etc., because this is the sacrament of unity and peace, as stated above (Q[73], A[4]; Q[79], A[1]). But in masses for the dead, in which the sacrifice is offered not for present peace, but for the repose of the dead, the "Pax" is omitted.
Then follows the reception of the sacrament, the priest receiving first, and afterwards giving it to others, because, as Dionysius says (Eccl. Hier. iii), he who gives Divine things to others, ought first to partake thereof himself.
Finally, the whole celebration of mass ends with the thanksgiving, the people rejoicing for having received the mystery (and this is the meaning of the singing after the Communion); and the priest returning thanks by prayer, as Christ, at the close of the supper with His disciples, "said a hymn" ( Mat. 26:30 ).
Reply to Objection 1: The consecration is accomplished by Christ's words only; but the other words must be added to dispose the people for receiving it, as stated above.
Reply to Objection 2: As is stated in the last chapter of John (verse 25), our Lord said and did many things which are not written down by the Evangelists; and among them is the uplifting of His eyes to heaven at the supper; nevertheless the Roman Church had it by tradition from the apostles. For it seems reasonable that He Who lifted up His eyes to the Father in raising Lazarus to life, as related in Jn. 11:41, and in the prayer which He made for the disciples ( Jn. 17:1 ), had more reason to do so in instituting this sacrament, as being of greater import.
The use of the word "manducate" instead of "comedite" makes no difference in the meaning, nor does the expression signify, especially since those words are no part of the form, as stated above (Q[78], A[1], ad 2,4).
The additional word "all" is understood in the Gospels, although not expressed, because He had said ( Jn. 6:54 ): "Except you eat the flesh of the Son of Man . . . you shall not have life in you."
Reply to Objection 3: The Eucharist is the sacrament of the unity of the whole Church: and therefore in this sacrament, more than in the others, mention ought to be made of all that belongs to the salvation of the entire Church.
Reply to Objection 4: There is a twofold instruction in the Faith: the first is for those receiving it for the first time, that is to say, for catechumens, and such instruction is given in connection with Baptism. The other is the instruction of the faithful who take part in this sacrament; and such instruction is given in connection with this sacrament. Nevertheless catechumens and unbelievers are not excluded therefrom. Hence in De Consecr., dist. 1, it is laid down: "Let the bishop hinder no one from entering the church, and hearing the word of God, be they Gentiles, heretics, or Jews, until the mass of the Catechumens begins," in which the instruction regarding the Faith is contained.
Reply to Objection 5: Greater devotion is required in this sacrament than in the others, for the reason that the entire Christ is contained therein. Moreover, this sacrament requires a more general devotion, i.e. on the part of the whole people, since for them it is offered; and not merely on the part of the recipients, as in the other sacraments. Hence Cyprian observes (De Orat. Domin. 31), "The priest, in saying the Preface, disposes the souls of the brethren by saying, 'Lift up your hearts,' and when the people answer---'We have lifted them up to the Lord,' let them remember that they are to think of nothing else but God."
Reply to Objection 6: As was said above (ad 3), those things are mentioned in this sacrament which belong to the entire Church; and consequently some things which refer to the people are sung by the choir, and same of these words are all sung by the choir, as though inspiring the entire people with them; and there are other words which the priest begins and the people take up, the priest then acting as in the person of God; to show that the things they denote have come to the people through Divine revelation, such as faith and heavenly glory; and therefore the priest intones the "Creed" and the "Gloria in excelsis Deo." Other words are uttered by the ministers, such as the doctrine of the Old and New Testament, as a sign that this doctrine was announced to the peoples through ministers sent by God. And there are other words which the priest alone recites, namely, such as belong to his personal office, "that he may offer up gifts and prayers for the people" ( Heb. 5:1 ). Some of these, however, he says aloud, namely, such as are common to priest and people alike, such as the "common prayers"; other words, however, belong to the priest alone, such as the oblation and the consecration; consequently, the prayers that are said in connection with these have to be said by the priest in secret. Nevertheless, in both he calls the people to attention by saying: "The Lord be with you," and he waits for them to assent by saying "Amen." And therefore before the secret prayers he says aloud, "The Lord be with you," and he concludes, "For ever and ever." Or the priest secretly pronounces some of the words as a token that regarding Christ's Passion the disciples acknowledged Him only in secret.
Reply to Objection 7: The efficacy of the sacramental words can be hindered by the priest's intention. Nor is there anything unbecoming in our asking of God for what we know He will do, just as Christ ( John 17:1 , 5 ) asked for His glorification.
But the priest does not seem to pray there for the consecration to be fulfilled, but that it may be fruitful in our regard, hence he says expressively: "That it may become 'to us' the body and the blood." Again, the words preceding these have that meaning, when he says: "Vouchsafe to make this oblation blessed," i.e. according to Augustine (Paschasius, De Corp. et Sang. Dom. xii), "that we may receive a blessing," namely, through grace; "'enrolled,' i.e. that we may be enrolled in heaven; 'ratified,' i.e. that we may be incorporated in Christ; 'reasonable,' i.e. that we may be stripped of our animal sense; 'acceptable,' i.e. that we who in ourselves are displeasing, may, by its means, be made acceptable to His only Son."
Reply to Objection 8: Although this sacrament is of itself preferable to all ancient sacrifices, yet the sacrifices of the men of old were most acceptable to God on account of their devotion. Consequently the priest asks that this sacrifice may be accepted by God through the devotion of the offerers, just as the former sacrifices were accepted by Him.
Reply to Objection 9: The priest does not pray that the sacramental species may be borne up to heaven; nor that Christ's true body may be borne thither, for it does not cease to be there; but he offers this prayer for Christ's mystical body, which is signified in this sacrament, that the angel standing by at the Divine mysteries may present to God the prayers of both priest and people, according to Apoc. 8:4 : "And the smoke of the incense of the prayers of the saints ascended up before God, from the hand of the angel." But God's "altar on high" means either the Church triumphant, unto which we pray to be translated, or else God Himself, in Whom we ask to share; because it is said of this altar ( Ex. 20:26 ): "Thou shalt not go up by steps unto My altar, i.e. thou shalt make no steps towards the Trinity." Or else by the angel we are to understand Christ Himself, Who is the "Angel of great counsel" ( Is. 9:6 : Septuagint), Who unites His mystical body with God the Father and the Church triumphant.
And from this the mass derives its name [missa]; because the priest sends [mittit] his prayers up to God through the angel, as the people do through the priest. or else because Christ is the victim sent [missa] to us: accordingly the deacon on festival days "dismisses" the people at the end of the mass, by saying: "Ite, missa est," that is, the victim has been sent [missa est] to God through the angel, so that it may be accepted by God.
Whether the actions performed in celebrating this sacrament are becoming?
Objection 1: It seems that the actions performed in celebrating this mystery are not becoming. For, as is evident from its form, this sacrament belongs to the New Testament. But under the New Testament the ceremonies of the old are not to be observed, such as that the priests and ministers were purified with water when they drew nigh to offer up the sacrifice: for we read ( Exod. 30:19 , 20 ): "Aaron and his sons shall wash their hands and feet . . . when they are going into the tabernacle of the testimony . . . and when they are to come to the altar." Therefore it is not fitting that the priest should wash his hands when celebrating mass.
Objection 2: Further, ( Ex. 30:7 ), the Lord commanded Aaron to "burn sweet-smelling incense" upon the altar which was "before the propitiatory": and the same action was part of the ceremonies of the Old Law. Therefore it is not fitting for the priest to use incense during mass.
Objection 3: Further, the ceremonies performed in the sacraments of the Church ought not to be repeated. Consequently it is not proper for the priest to repeat the sign of the cross many times over this sacrament.
Objection 4: Further, the Apostle says ( Heb. 7:7 ): "And without all contradiction, that which is less, is blessed by the better." But Christ, Who is in this sacrament after the consecration, is much greater than the priest. Therefore quite unseemingly the priest, after the consecration, blesses this sacrament, by signing it with the cross.