In the Magnificat Antiphon for Second Vespers of the Feast of Corpus Christi, the Church sings “O sacrum convívium, in quo Christus súmitur: recólitur memória passiónis eius: mens implétur grátia: et futúræ glóriæ nobis pignus datur, allelúia. / O sacred banquet, in which Christ is received, the memory of His Passion is renewed, the mind is filled with grace, and a pledge of future glory is given to us, alleluia.” This antiphon is also recited by the Priest when Holy Communion is distributed outside of Mass.
In the first place, the antiphon makes a declaration of belief in the true presence of Christ in the Holy Eucharist – “O sacred banquet, in which Christ is received.” For when the Priest prays the Words of Consecration over the offered bread and wine, they no longer remain bread and wine. They become really, truly, and substantially the Body and Blood, Soul and Divinity of the Incarnate Son of God, Christ the Lord. And so, when the Eucharist is received in Holy Communion, it is Christ Himself Who is received, whole and entire.
Next, the antiphon declares that the Eucharist signifies something past – “the memory of His Passion is renewed.” As all of the Sacraments receive their sanctifying power from the Passion and Death of the Lord, they all, in a way, make present the same (see S.T. III, q. 60, a. 3, c; q. 62, a. 5, c). But, in addition to the power of Our Lord’s Passion being present as with the other Sacraments, the Eucharist makes Our Lord’s Sacrifice present in another manner as well.
When the Priest prays the Words of Consecration, he does not consecrate the bread and the wine at the same time, but rather first the bread and then the wine. These separate Consecrations of the Body and Blood of the Lord present Christ as mystically slain, with His Body separated from His Blood as they were at His Death, making His bloody Sacrifice on the Cross present in an unbloody, sacramental manner. But even when the Mass is completed, the Hosts which remain and which are adored and later received, as they were consecrated as part of the Eucharistic Sacrifice, maintain a connection with the Sacrifice of the Mass, and thus with Christ’s Sacrifice on the Cross. This being the case, the Eucharistic Host, even outside of Mass, can serve to recall to the mind of the Faithful Christ’s Passion and Death.
“The mind is filled with grace” signifies something present, namely the grace which the Faithful can receive in the reception of Eucharistic Communion. For, like all of the Sacraments, in the reception of Holy Communion, the Faithful receive an increase of Sanctifying Grace proportional to their dispositions. Along with Sanctifying Grace, effects particular to Holy Communion are also conferred.
The antiphon closes by looking towards the future – “a pledge of future glory is given to us.” Our Lord has promised “he that eateth my flesh and drinketh my blood hath everlasting life” (John 6:55). Now “everlasting life” is the life of glory. The Eucharist, however, can only currently be a pledge of the life of glory because one cannot perfectly and without the fear of loss possess spiritual goods in this current life. This is reserved for those who pass from this world to the next in a state of grace. But while “everlasting life” is not possessed perfectly in this life, it is possessed in some way, that is, as a beginning and a pledge. For the life of glory is the final blossoming of the life of grace started here below. And so, those who receive the Blessed Sacrament receive, in the present effects mentioned above, the seed, the pledge of the future final effect, the life of glory, which will be obtained by those who persevere (see S.T. III, q. 79, a. 2).
The Catechism of the Council of Trent (also known as The Roman Catechism) treats these points in the following manner (TAN Hardcover 1982 Edition, pp. 230-231):
“It must, therefore, be diligently explained what the Sacrament of the Eucharist signifies, that the faithful, beholding the sacred mysteries with their eyes, may also at the same time feed their souls with the contemplation of divine things. Three things, then, are signified by this Sacrament. The first is the Passion of Christ Our Lord, a thing past; for He Himself said: Do this for a commemoration of me (Luke 22:19), and the Apostle [Paul] says: As often as you shall eat this bread, and drink the chalice, you shall show the death of the Lord, until he come. (1 Cor. 11:26).”
It is also significant of divine and heavenly grace, which is imparted at the present time by this Sacrament to nurture and preserve the soul. Just as in Baptism we are begotten unto newness of life and by Confirmation are strengthened to resist Satan and openly to profess the name of Christ, so by the Sacrament of the Eucharist are we nurtured and supported.
It is, thirdly, a foreshadowing of future eternal joy and glory, which, according to God’s promises, we shall receive in our heavenly country.
These three things, then, which are clearly distinguished by their reference to past, present and future times, are so well represented by the Eucharistic mysteries that the whole Sacrament, though consisting of different species, signifies the three as if it referred to one thing only.
Let the reader resolve, then, to frequently bring these reflections to mind when in the presence of the Blessed Sacrament, and even more so at the reception of Holy Communion.