Treatise: On the Most Holy Eucharist

S. Th. III, q. 73, a. 4 and 6.

197. The third sacrament is the Most Holy Eucharist. - For just as first in Baptism we must be reborn unto spiritual and divine life, then in it be strengthened through Confirmation and, as it were, grow unto perfect age, so through the whole of life we must be nourished in divine life, which is done through the Holy Eucharist.

198. The Eucharist is the most perfect sacrament of all, as was declared above, n. 101, so that the other sacraments are ordered to it as to an end. Hence by excellence it is called the most holy, venerable sacrament, sacrament of sacraments, or simply the Most Holy; likewise gift, holy gifts, tremendous mysteries, etc.; and therefore it has also been accustomed to be called by many names. For the dignity and perfection of this sacrament is so great that it cannot be expressed by one name, whence they have attempted to express it by several words. For:

A. Every sacrament is a sign commemorative of the Passion of Christ, demonstrative of grace, and prognostic of future glory. Now the Eucharist, 1. as a sign commemorative of the Passion of Christ, is called sacrifice, victim, sacrament of our price, new testament, memorial of redemption, holocaust of salvation, etc.; 2. as demonstrative of the union of the soul with Christ and of the members of the Church among themselves, is called communion, synaxis, mystery of peace and unity, sacrament of love, etc.; 3. as prognostic of the enjoyment of God in the fatherland, is called viaticum, because here it furnishes us the way of arriving there; likewise pledge of eternal inheritance. - Generally it is called Eucharist, i.e. good grace, because Christ in its very institution gave thanks, and it is the best act of thanksgiving offered daily to God, and because it is good grace by excellence, since it contains Christ as the fountain of all grace, charity, and eternal life.¹ This name is the principal and most ancient.²

¹ Whence St. Bonaventure, De inst. novit.: "this sacrament is the memorial of His whole love and, as it were, a certain compendium of all His benefits."

² Thus already in the Didache and in St. Justin.

B. Likewise, just as in every sacrament, so also in the Eucharist three things are distinguished: sacrament only, or the external sign, which only signifies and is not signified; reality and sacrament, which is signified and at the same time signifies; reality only, or the effect of grace, which is signified and does not signify. The sacrament only is the consecrated species of bread and wine, or the species informed by the words of consecration, which signify the body and blood of Christ present under the aspect of food and drink; the reality and sacrament are the body and blood of Christ, whose presence is signified by the species and which signify the spiritual refreshment of the soul; the reality is the spiritual refreshment itself of the soul through divine grace.³ Now, 1. by reason of the external sign which is the sacrament only, it is called bread of life, holy bread, bread of angels, supersubstantial bread, bread which descended from heaven, - wine generating virgins, chalice of blessing, mystical eulogy or blessing and consecration; 2. by reason of the contained reality which at the same time is sacrament: body, flesh, blood of Christ, sacrament of the body and blood of the Lord, holy things, holy of holies, holy thing of the Lord, the good itself (τὸ ἀγαθόν), the perfect itself (τὸ τέλειον); 3. by reason of the effects which are the reality of the sacrament: sacrament of grace, saving grace, life, food of souls, nourishment of eternal life, sustenance, medicine and drink of immortality, etc.

³ Very well known are the words of Innocent III, Decr. l. 3, tit. 41, c. 6: "It is useful to distinguish among three things which are distinct in this sacrament, namely the sensible form, the truth of the body, and the special power. The form is of bread and wine, the truth of flesh and blood, the power of unity and charity. The first is sacrament and not reality, the second is sacrament and reality, the third is reality and not sacrament."

C. Finally, by reason of the circumstances in which it was instituted or is ministered, the Eucharist is called sacred supper, supper of the Lord, table of the Lord, heavenly table, mystical table, sacred banquet, agapae, metalepsis (i.e. assumption), sacrament of the altar, divine feasts, breaking of bread.

It is also called mystery of faith, because it is the greatest mystery to be held by faith alone, and because in one compendium the Eucharist at the same time embraces the principal divine mysteries.

199. The manifold excellence of the Eucharist was also foretold by various figures. - For:

1. As to that which is sacrament only, the chief figure was the oblation of Melchisedech, who offered bread and wine (Gen. XIV, 18); also the loaves of firstfruits (Lev. XXIII, 10) and of proposition (XXIV, 5), and the multiplication of loaves done by Christ (John VI; Mark VI and VIII).

2. As to Christ suffering, who is contained in the sacrament and thus is reality and sacrament, the figures are all the sacrifices of the Old Law, chiefly the sacrifice of expiation (Lev. XVI) and the blood of the testament (Ex. XXIV, 8).

3. As to the effect or reality of the sacrament, its principal figure was manna, which had in itself every delight and sweetness of taste (Ex. XVI, 13; Num. XI, 7); likewise the tree of life (Gen. II, 9), the hearth-cake of Elias (Judg. VII, 13; III Kings XIX, 6, 8), the jar of meal which was not exhausted (III Kings XVII, 16).

But the principal figure is the Paschal Lamb, which prefigured it as to these three things: as to the first, because it was eaten with unleavened bread; as to the second, because it was immolated by the whole people of Israel at the time of Passover, which is the figure of the immolation of Christ on the cross; as to the third, because by the blood of the Paschal Lamb the children of Israel were protected from the devastating Angel and led out of Egyptian servitude.

200. There is a twofold aspect of the Eucharist, because it is at once sacrament and sacrifice. - The Eucharist can be considered either with respect to men, whom it sanctifies, and under this aspect it is a sacrament, or with respect to God, whom it honors, or to His worship, and thus it is a sacrifice. Whence the treatise is divided into two sections, of which one treats of the sacrament itself, the other of the sacrifice, in which its minister and rite also will be discussed.