1322 The holy Eucharist completes Christian initiation. Those who have been raised to the dignity of the royal priesthood by Baptism and configured more deeply to Christ by Confirmation participate with the whole community in the Lord's own sacrifice by means of the Eucharist.
1323 "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.'"
1324 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."
1325 "The Eucharist is the efficacious sign and sublime cause of that communion in the divine life and that unity of the People of God by which the Church is kept in being. It is the culmination both of God's action sanctifying the world in Christ and of the worship men offer to Christ and through him to the Father in the Holy Spirit."
1326 Finally, by the Eucharistic celebration we already unite ourselves with the heavenly liturgy and anticipate eternal life, when God will be all in all.
1333 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.
1334 In the Old Covenant bread and wine were offered in sacrifice among the first fruits of the earth as a sign of grateful acknowledgment to the Creator. But they also received a new significance in the context of the Exodus: the unleavened bread that Israel eats every year at Passover commemorates the haste of the departure that liberated them from Egypt; the remembrance of the manna in the desert will always recall to Israel that it lives by the bread of the Word of God; their daily bread is the fruit of the promised land, the pledge of God's faithfulness to his promises. The "cup of blessing" at the end of the Jewish Passover meal adds to the festive joy of wine an eschatological dimension: the messianic expectation of the rebuilding of Jerusalem. When Jesus instituted the Eucharist, he gave a new and definitive meaning to the blessing of the bread and the cup.
1336 The first announcement of the Eucharist divided the disciples, just as the announcement of the Passion scandalized them: "This is a hard saying; who can listen to it?" The Eucharist and the Cross are stumbling blocks. It is the same mystery and it never ceases to be an occasion of division. "Will you also go away?": the Lord's question echoes through the ages, as a loving invitation to discover that only he has "the words of eternal life" and that to receive in faith the gift of his Eucharist is to receive the Lord himself.
1337 The Lord, having loved those who were his own, loved them to the end. Knowing that the hour had come to leave this world and return to the Father, in the course of a meal he washed their feet and gave them the commandment of love. In order to leave them a pledge of this love, in order never to depart from his own and to make them sharers in his Passover, he instituted the Eucharist as the memorial of his death and Resurrection, and commanded his apostles to celebrate it until his return; "thereby he constituted them priests of the New Testament."
1340 By celebrating the Last Supper with his apostles in the course of the Passover meal, Jesus gave the Jewish Passover its definitive meaning. Jesus' passing over to his father by his death and Resurrection, the new Passover, is anticipated in the Supper and celebrated in the Eucharist, which fulfills the Jewish Passover and anticipates the final Passover of the Church in the glory of the kingdom.
1341 The command of Jesus to repeat his actions and words "until he comes" does not only ask us to remember Jesus and what he did. It is directed at the liturgical celebration, by the apostles and their successors, of the memorial of Christ, of his life, of his death, of his Resurrection, and of his intercession in the presence of the Father.
1342 From the beginning the Church has been faithful to the Lord's command. Of the Church of Jerusalem it is written:
They devoted themselves to the apostles' teaching and fellowship, to the breaking of bread and the prayers. . . . Day by day, attending the temple together and breaking bread in their homes, they partook of food with glad and generous hearts.1345 As early as the second century we have the witness of St. Justin Martyr for the basic lines of the order of the Eucharistic celebration. They have stayed the same until our own day for all the great liturgical families. St. Justin wrote to the pagan emperor Antoninus Pius (138-161) around the year , explaining what Christians did:
On the day we call the day of the sun, all who dwell in the city or country gather in the same place.1346 The liturgy of the Eucharist unfolds according to a fundamental structure which has been preserved throughout the centuries down to our own day. It displays two great parts that form a fundamental unity:
The memoirs of the apostles and the writings of the prophets are read, as much as time permits.
When the reader has finished, he who presides over those gathered admonishes and challenges them to imitate these beautiful things.
Then we all rise together and offer prayers* for ourselves . . .and for all others, wherever they may be, so that we may be found righteous by our life and actions, and faithful to the commandments, so as to obtain eternal salvation.
When the prayers are concluded we exchange the kiss.
Then someone brings bread and a cup of water and wine mixed together to him who presides over the brethren.
He takes them and offers praise and glory to the Father of the universe, through the name of the Son and of the Holy Spirit and for a considerable time he gives thanks (in Greek: eucharistian) that we have been judged worthy of these gifts.
When he has concluded the prayers and thanksgivings, all present give voice to an acclamation by saying: 'Amen.'
When he who presides has given thanks and the people have responded, those whom we call deacons give to those present the "eucharisted" bread, wine and water and take them to those who are absent.
- the gathering, the liturgy of the Word, with readings, homily and general intercessions;The liturgy of the Word and liturgy of the Eucharist together form "one single act of worship"; the Eucharistic table set for us is the table both of the Word of God and of the Body of the Lord.
- the liturgy of the Eucharist, with the presentation of the bread and wine, the consecratory thanksgiving, and communion.