Some clever men imagine that the Lord's Supper was instituted for two reasons. First, that it might be a mark and testimony of profession, just as a particular shape of hood is the sign of a particular profession. Then they think that such a mark was especially pleasing to Christ, namely, a feast to signify mutual union and friendship among Christians, because banquets are signs of covenant and friendship. But this is a secular view; neither does it show the chief use of the things delivered by God; it speaks only of the exercise of love, which men, however profane and worldly, understand, it does not speak of faith, the nature of which few understand.
The Sacraments are signs of God's will toward us, and not merely signs of men among each other, and they are right in defining that Sacraments in the New Testament are signs of grace. And because in a sacrament there are two things, a sign and the Word, the Word, in the New Testament, is the promise of grace added. The promise of the New Testament is the promise of the remission of sins, as the text, Luke 22, 19, says: This is My body, which is given for you. This cup is the New Testament in My blood which is shed for many for the remission of sins. Therefore the Word offers the remission of sins. And a ceremony is, as it were, a picture or seal, as Paul, Rom.4, 11, calls it, of the Word, making known the promise. Therefore, just as the promise is useless unless it is received by faith, so a ceremony is useless unless such faith is added as is truly confident that the remission of sins is here offered. And this faith encourages contrite minds. And just as the Word has been given in order to excite this faith, so the Sacrament has been instituted in order that the outward appearance meeting the eyes might move the heart to believe [and strengthen faith]. For through these, namely, through Word and Sacrament, the Holy Ghost works.
And such use of the Sacrament, in which faith quickens terrified hearts, is a service of the New Testament, because the New Testament requires spiritual dispositions, mortification and quickening. [For according to the New Testament the highest service of God is rendered inwardly in the heart.] And for this use Christ instituted it, since He commanded them thus to do in remembrance of Him. For to remember Christ is not the idle celebration of a show [not something that is accomplished only by some gestures and actions], or one instituted for the sake of example, as the memory of Hercules or Ulysses is celebrated in tragedies, but it is to remember the benefits of Christ and receive them by faith so as to be quickened by them. Psalm 111, 4.5 accordingly says: He hath made His wonderful works to be remembered: the Lord is gracious and full of compassion. He hath given meat unto them that fear Him. For it signifies that the will and mercy of God should be discerned in the ceremony. But that faith which apprehends mercy quickens. And this is the principal use of the Sacrament, in which it is apparent who are fit for the Sacrament, namely, terrified consciences and how they ought to use it.
The sacrifice [thank-offering or thanksgiving] also is added. For there are several ends for one object. After conscience encouraged by faith has perceived from what terrors it is freed, then indeed it fervently gives thanks for the benefit and passion of Christ, and uses the ceremony itself to the praise of God, in order by this obedience to show its gratitude; and testifies that it holds in high esteem the gifts of God. Thus the ceremony becomes a sacrifice of praise.
And the Fathers, indeed, speak of a twofold effect, of the comfort of consciences, and of thanksgiving, or praise. The former of these effects pertains to the nature [the right use] of the Sacrament; the latter pertains to the sacrifice. Of consolation Ambrose says: Go to Him and be absolved, because He is the remission of sins. Do you ask who He is? Hear Him when He says, John 6, 35: I am the Bread of life; he that cometh to Me shall never hunger; and he that believeth on Me shall never thirst. This passage testifies that in the Sacrament the remission of sins is offered; it also testifies that this ought to be received by faith. Infinite testimonies to this effect are found in the Fathers, all of which the adversaries pervert to the opus operatum, and to a work to be applied on behalf of others; although the Fathers clearly require faith, and speak of the consolation belonging to every one, and not of the application.
Besides these, expressions are also found concerning thanksgiving, such as that most beautifully said by Cyprian concerning those communing in a godly way. Piety, says he, in thanksgiving the Bestower of such abundant blessing, makes a distinction between what has been given and what has been forgiven, i.e., piety regards both what has been given and what has been forgiven, i.e., it compares the greatness of God's blessings and the greatness of our evils, sin and death, with each other, and gives thanks, etc. And hence the term eucharist arose in the Church. Nor indeed is the ceremony itself, the giving of thanks ex opere operato, to be applied on behalf of others, in order to merit for them the remission of sins, etc., in order to liberate the souls of the dead. These things conflict with the righteousness of faith, as though, without faith, a ceremony can profit either the one performing it or others.