Catholics believe the Eucharist, or Communion, is both a sacrifice and a meal. We believe in the real presence of Jesus, who died for our sins. As we receive Christ's Body and Blood, we also are nourished spiritually and brought closer to God.
Amen, amen, I say to you, unless you eat the flesh of the Son of Man and drink His blood, you do not have life within you. Whoever eats My flesh and drinks My blood has eternal life, and I will raise him on the last day. (John 6: 53-54)
Jesus took bread, said the blessing, broke it, and giving it to His disciples said, "Take and eat; this is My body." Then He took a cup, gave thanks, and gave it to them, saying, "Drink from it, all of you, for this is My blood of the covenant, which will be shed on behalf of many for the forgiveness of sins." (Matthew 26: 26-28)
"I am the living bread that came down from heaven; whoever eats this bread will live forever; and the bread that I will give is my flesh for the life of the world . . . Amen, amen, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you do not have life within you. Whoever eats my flesh and drinks my blood has eternal life, and I will raise him on the last day. For my flesh is true food, and my blood is true drink. Whoever eats my flesh and drinks my blood remains in me and I in him." (John 6: 51, 53-56)
"Jesus is present in various ways: in His people, in His word, in the poor and needy and suffering, and in many other ways. But He is fully present in the Eucharist. It is, says G. K. Chesterton, the difference between saying “The spirit of God pervades the universe” and saying “Jesus Christ just walked into the room.”
The simplest way to express what Christ asks us to believe about the Real Presence is that the Eucharist is really He. The Real Presence is the real Jesus. We are to believe that the Eucharist began in the womb of the Virgin Mary; that the flesh which the Son of God received from His Mother at the Incarnation is the same flesh into which He changed bread at the Last Supper; that the blood He received from His Mother is the same blood into which He changed wine at the Last Supper. Had she not given Him His flesh and blood there could not be a Eucharist.
At the Last Supper, on the night he was betrayed, our Savior instituted the Eucharistic sacrifice of his Body and Blood. This he did in order to perpetuate the sacrifice of the cross throughout the ages until he should come again, and so to entrust to his beloved Spouse, the Church, a memorial of his death and resurrection: a sacrament of love, a sign of unity, a bond of charity, a Paschal banquet in which Christ is consumed, the mind is filled with grace, and a pledge of future glory is given to us. (CCC 1323)
The Eucharist is "the source and summit of the Christian life." "The other sacraments, and indeed all ecclesiastical ministries and works of the apostolate, are bound up with the Eucharist and are oriented toward it. For in the blessed Eucharist is contained the whole spiritual good of the Church, namely Christ himself, our Pasch." (CCC 1324)
At the heart of the Eucharistic celebration are the bread and wine that, by the words of Christ and the invocation of the Holy Spirit, become Christ's Body and Blood. Faithful to the Lord's command the Church continues to do, in his memory and until his glorious return, what he did on the eve of his Passion: "He took bread. . . ." "He took the cup filled with wine. . . ." The signs of bread and wine become, in a way surpassing understanding, the Body and Blood of Christ; they continue also to signify the goodness of creation. Thus in the Offertory we give thanks to the Creator for bread and wine, fruit of the "work of human hands," but above all as "fruit of the earth" and "of the vine"—gifts of the Creator. The Church sees in the gesture of the king-priest Melchizedek, who "brought out bread and wine," a prefiguring of her own offering. (CCC 1333)
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Holy Communion Miracles of the Holy Eucharist
How is Jesus present in the Eucharist? Most of us, at one time or another, find ourselves either asking that question or trying to explain the mystery for someone else. Catholics believe that the Body and Blood of Jesus is present in consecrated bread and wine. We do not say the Eucharist is like the body and blood of Jesus, but that it is the body and blood of Jesus. In the Gospels Jesus says, "This is my body" and "This is my blood." That is strong language. It is language which Christians have sought to understand for many centuries.
It is particularly fitting that Christ should come to us in the Eucharist, write the bishops, for "Jesus Christ gives himself to us in a form that employs the symbolism inherent in eating bread and drinking wine. Furthermore, being present under the appearances of bread and wine, Christ gives himself to us in a form that is appropriate for human eating and drinking. Also, this kind of presence corresponds to the virtue of faith, for the presence of the Body and Blood of Christ cannot be detected or discerned by any way other than faith."
The bishops here are reminding us that, even though real—not merely symbolic—change has taken place, there is still tremendous symbolism at work. All sacraments use symbols, because symbols help us to understand the deepest connections between things.
Throughout the history of the Catholic Church, Jesus has proven beyond any doubt that He is truly present in the Holy Eucharist. Why did He have to prove this to us? It is because at certain times in history, there were heresies that denied the Real Presence in the Sacrament of the Holy Eucharist. On other occasions, some priests doubted the Real Presence of Jesus in the Holy Eucharist. And yet, on other occasions, the Holy Eucharist was abused by believers and non-believers alike.
Because God is truly present in the consecrated species of bread and wine, we must preserve the sacred gifts with the greatest reverence and worship our Lord and Redeemer in the Most Blessed Sacrament.
If there are consecrated hosts left over after the celebration of Holy Eucharist, they are kept in sacred vessels in the tabernacle. Since the Most Blessed Sacrament is present in them, the tabernacle is one of the most venerable places in every church. We genuflect before any tabernacle. Certainly, anyone who is really following Christ will recognize him in the poorest of the poor and serve him in them. But he will also find time to spend in adoration before the tabernacle and offer his love to our Eucharistic Lord. (YOUCAT question 218).
Eucharistic Adoration is the respect and worship we give to Jesus, who is truly present to us in the Holy Eucharist under the appearances of bread and wine. Christians have adored Jesus in the Holy Eucharist for as long as the Church has celebrated the Eucharist -- that is, from the time of the Apostles.