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The Mystery of Transubstantiation and Sacramental Grace


The Catechism notes that “from the beginning the Church has been faithful to the Lord’s command” (CCC #1342). As we read in the Acts of the Apostles 2:42, “they held steadfastly to the apostles’ teaching and fellowship, to the breaking of the bread and to the prayers.” The “breaking of the bread” here refers to the Eucharistic bread which, although it retains the appearance of bread, becomes Christ himself in reality. Now this is where many Catholics have difficulty. How is it that the bread becomes Christ? Is this merely symbolic, or are we speaking of a real transformation?

The Catechism explains that “The mode of Christ’s presence under the Eucharistic species is unique. It raises the Eucharist above all the sacraments as ‘the perfection of the spiritual life and the end to which all the sacraments tend.’ In the most blessed sacrament of the Eucharist ‘the body and blood, together with the soul and divinity, of our Lord Jesus Christ and, therefore, the whole Christ is truly, really, and substantially contained.’” [And they cite Mysterium fidei, an encyclical on the Eucharist by Pope Paul VI, who declares, “This presence is called ‘real’ - by which is not intended to exclude the other types of presence [of Christ] as if they could not be ‘real’ too, but because it is presence in the fullest sense: that is to say, it is a substantial presence by which Christ, God and man, makes himself wholly and entirely present’” (MF 39, cited at CCC # 1374). And lest we doubt God’s power to do this, St. Ambrose asks us, “Could not Christ’s word, which can make from nothing what did not exist, change existing things into what they were not before? It is no less a feat to give things their original nature than to change their nature” (De myst 9, 50; 52: PL 16, 405-407; in CCC #1375).


The Catechism also cites the Council of Trent’s Decree on the Eucharist, which states, “Because Christ our Redeemer said that it was truly his body that he was offering under the species of bread, it has always been the conviction of the Church of God, and this holy Council now declares again, that by the consecration of the bread and wine there takes place a change of the whole substance of the bread into the substance of the body of Christ our Lord and of the whole substance of the wine into the substance of his blood. This change the holy Catholic Church has fittingly and properly called transubstantiation” (Council of Trent (1551): DS 1642, in CCC #1376). Transubstantiation, a change of substance. The substance of bread and wine change into the substance of Christ himself (body, blood, soul, and divinity), even while the bread and wine retain their properties, or accidents, so that they continue to look, taste and feel like bread and wine, and would appear that way even when chemically tested as well, with the exception of certain Eucharistic miracles, in which sometimes God has made the reality of this hidden change become more manifest externally.


But ordinarily, the transubstantiation is hidden to our senses and is something only known by the grace of God moving the soul to faith. But even when one believes in the real and substantial presence of Christ in the Eucharist, one may still have certain questions that it is good to consider. For example, if I break a consecrated host am I breaking Jesus? The Catechism answers this question by saying that “the Eucharistic presence of Christ begins at the moment of the consecration and endures as long as the Eucharistic species subsist. Christ is present whole and entire in each of the species [i.e., in the bread and wine] and whole and entire in each of their parts, in such a way that the breaking of the bread does not divide Christ” (CCC #1377). So no matter how tiny the pieces of consecrated bread or drops of consecrated wine, the entire Christ is present there whole and entire, not mingled with bread and wine, but with their substance having been changed by Christ into himself, so that although their properties remain, the bread and wine themselves are no longer present, but it is Christ who is present in a hidden way. It is really a miracle that the appearances or properties of the original bread and wine remain, while the original substances are, in fact, no longer there.


St. Thomas Aquinas articulates this mystery in the following way. He says, “Christ’s body is in this sacrament substantively, that is, in the way in which substance is under dimensions, but not after the manner of dimensions…. Now it is evident that the whole nature of a substance is under every part of the dimensions under which it is contained; just as the entire nature of air is under every part of air, and the entire nature of bread under every part of bread…. And therefore it is manifest that the entire Christ is under every part of the species of the bread, even while the host remains entire, and not merely when it is broken” (ST III, q. 76, a. 3, corp.) Perhaps one might take also the example of water, H2O. It is true that the entire substance of water is found in even the smallest droplet of water. Similarly, the entire Christ is found in each particle of the consecrated bread or each drop of the consecrated wine, no matter how small.


We might still wonder, however, how it is that Christ can be entirely present in each consecrated host around the world. Is he jumping about from host to host? No. Because of the fact that Christ is in the Eucharist under the mode [or manner] of substance rather than under the dimensive quantity of place, he is able to remain, in his human nature, in heaven, and so transforms every consecrated host or wine into himself without he himself being subject to any local movement whatsoever. In other words, although by divine power, the consecrated bread or wine are really and substantially transformed into Christ, Christ himself is not moved when the consecrated bread or wine are moved, just as neither can he be harmed, by one eating the consecrated bread or wine which have been transformed into himself. Christ is substantially and really present, yet he is not affected by the sacrament. That is, this sacrament does not alter or change Christ himself in any way. Rather, his being in this sacrament transforms us when we receive it worthily.


In other words, Christ remains incorruptible and glorious in heaven, but, the species of bread and wine have been substantially transformed into Christ’s body and blood, and consequently also transform those persons who receive them worthily, that is, those who are not conscious of any serious or mortal sin, for which the person has not already sought for and received forgiveness from God.


Now, as I have said, the Church teaches that the Eucharist is truly Christ, and yet, one can and should also say that the Eucharist is a sign. To say that the Eucharist is a sign may shock some Catholics who may think, wait a minute, the Eucharist is truly Christ, how then can you say it is a sign? This is because we often think of a sign as being merely a symbol, rather than as being a reality itself. But the Eucharist is a sacrament, and a sacrament is a sign. What are the initial signs? First, we have the bread and the wine, common foods that provide nourishment. Secondly, this nourishment takes two forms: bread which gives us strength, and wine which gladdens the heart and relieve us of some of the burden of the day, so also when changed into the body and blood of Christ, the Eucharistic bread strengthens us spiritually and the wine of the Eucharist, once changed into Christ, relieves us of the burden of sin and so gladdens our hearts. Wine is also used to celebrate weddings, as we see at the wedding feast of Cana, where Christ changes water into wine, since they had run out. So also, the wine changed into Christ’s blood gladdens us with the presence of the true Bridegroom of our souls. Finally, there is the duality of the sacrament: bread and wine are consecrated separately during the Mass, thus signifying the separation of Christ’s body and blood at the moment of his passion and death.


So the Eucharist, while being truly and substantially Christ himself, body, blood, soul, and divinity, is a reality which is a sign of another reality. In fact, for St. Thomas Aquinas, that is precisely what a sign is: a reality which signifies another reality. So all the sacraments instituted by Christ are signs, but they are signs that actually give what they signify. So if we look at what the sacrament signifies, we will know what it gives. In other words, the realities that are given by each sacrament are found within the sacrament itself, and the realities which are signified are the graces of the sacrament. Of course, the Eucharist is unique in that Christ not only gives us grace in the sacrament, but he gives us his very self, as we have seen. As Aquinas implies, the Eucharist is a continuation of the Incarnation of Christ. And in fact, we know that it is really, truly, and substantially the body and blood of Christ, because he himself told us so, and we take him at his word. This is my body; This is my blood. It is truly Christ himself. So Christ has not abandoned us. His incarnation continues in the gift of the Eucharist. But let us ask, then, what other reality does the Eucharist point toward and signify? It is the reality of the sacramental grace and effects that the Eucharist gives those who receive it worthily. And the Catechism calls these sacramental graces and effects the fruits of Holy Communion.


So what are these fruits? First, says the Catechism, “Holy Communion augments our union with Christ. The principal fruit of receiving the Eucharist in Holy Communion is an intimate union with Christ Jesus [since we receive Christ himself]. Indeed, the Lord said: ‘He who eats my flesh and drinks my blood abides in me, and I in him’[Jn 6:56]” (CCC n. 1391). So, the Catechism continues, “What material food produces in our bodily life, Holy Communion wonderfully achieves in our spiritual life. Communion with the flesh of the risen Christ, a flesh ‘given life and giving life through the Holy Spirit,’ preserves, increases, and renews the life of grace received at Baptism. This growth in Christian life needs the nourishment of Eucharistic Communion” (CCC n. 1392). Now eating Christ’s body and drinking Christ’s blood is not a strange form of cannibalism, since we are eating his body and drinking his blood under the appearances of bread and wine. In eating Christ’s body, we not only assimilate him, but we are assimilated into him, united with him, transformed by him, divinized or made like God by his grace, and in drinking his blood, we receive the grace of salvation from the side of Christ who pours himself out for us on the cross.


The second fruit, according to the Catechism, is that “Holy Communion separates us from sin. The body of Christ we receive in Holy Communion is ‘given up for us,’ and the blood we drink ‘shed for the many for the forgiveness of sins’” (CCC n. 1393). What this means, teaches the Catechism, is that “As bodily nourishment restores lost strength, so the Eucharist strengthens our charity, which tends to be weakened in daily life; and this living charity wipes away venial sins. By giving himself to us Christ revives our love and enables us to break our disordered attachments to creatures and root ourselves in him…. [n. 1394] By the same charity that it enkindles in us, the Eucharist preserves us from future mortal sins. The more we share the life of Christ and progress in his friendship, the more difficult it is to break away from him by mortal sin. The Eucharist is not ordered to the forgiveness of mortal sins – that [we have seen] is proper to the sacrament of Reconciliation. The Eucharist is properly the sacrament of those who are [already] in full communion with the Church” (n. 1395).


And that is actually a third fruit of the Eucharist: it strengthens the unity of the Mystical Body, which is the Church. The Catechism teaches that “the Eucharist makes the Church. Those who receive the Eucharist are united more closely to Christ. Through it Christ unites them to all the faithful in one body - the Church. Communion renews, strengthens, and deepens this incorporation into the Church, already achieved by Baptism. In Baptism we have been called to form but one body. The Eucharist fulfils this call” (n. 1396). And in it we also pray for the unity of all Christians.

In addition, “The Eucharist commits us to the poor [according to the Catechism.] To receive in truth the Body and Blood of Christ given up for us, we must recognize Christ in the poorest, his brethren” (n. 1397).


Finally, the Eucharist is the “pledge of the glory to come.” The Catechism points out that “In an ancient prayer the Church acclaims the mystery of the Eucharist: [saying] ‘O sacred banquet in which Christ is received as food, the memory of his Passion is renewed, the soul is filled with grace and a pledge of the life to come is given to us.’ If the Eucharist is the memorial of the Passover of the Lord Jesus, if by our communion at the altar we are filled ‘with every heavenly blessing and grace,’ then the Eucharist is also an anticipation of the heavenly glory” (n. 1402). The Catechism continues, “There is no surer pledge or dearer sign of this great hope in the new heavens and new earth in which righteousness dwells,’ than the Eucharist. Every time this mystery is celebrated, [as St. Ignatius of Antioch says, Ad Eph 20,2] ‘the work of our redemption is carried on’ and we ‘break the one bread that provides the medicine of immortality, the antidote for death, and the food that makes us live forever in Jesus Christ’” (CCC n. 1405).


So let us ask the Holy Spirit to help us ponder and contemplate these truths regarding the sacrament of the Eucharist, and may we grow in faith, hope, and charity, believing in Christ’s real presence, hoping in his assistance, and loving him more and more, until we shall see him as he really is, face to face in paradise.




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