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The Real Presence of Jesus Christ in the Sacrament of the Eucharist: Basic Questions and Answers
http://www.usccb.org/prayer-and-worship/the-mass/order-of-mass/liturgy-of-the-eucharist/the-real-presence-of-jesus-christ-in-the-sacrament-of-the-eucharist-basic-questions-and-answers.cfm
The Real Presence of Jesus Christ in the Sacrament of the Eucharist: Basic Questions and Answers
Produced by the Committee on Doctrine of the United States Conference of Catholic Bishops and approved by the full body of bishops at their June 2001 General Meeting. The text is authorized for publication by the undersigned.
Monsignor William P. Fay
General Secretary, USCCB
Introduction
The Lord Jesus, on the night before he suffered on the cross, shared one last meal with his disciples. During this meal our Savior instituted the sacrament of his Body and Blood. He did this in order to perpetuate the sacrifice of the Cross throughout the ages and to entrust to the Church his Spouse a memorial of his death and resurrection. As the Gospel of Matthew tells us:
While they were eating, 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.” (Mt 26:26-28; cf. Mk 14:22-24, Lk 22:17-20, 1 Cor 11:23-25)
Conclusion
By his Real Presence in the Eucharist Christ fulfils his promise to be with us “always, until the end of the age” (Mt 28:20). As St. Thomas Aquinas wrote, “It is the law of friendship that friends should live together. . . . Christ has not left us without his bodily presence in this our pilgrimage, but he joins us to himself in this sacrament in the reality of his body and blood” ( Summa Theologiae, III q. 75, a. 1). With this gift of Christ’s presence in our midst, the Church is truly blessed. As Jesus told his disciples, referring to his presence among them, “Amen, I say to you, many prophets and righteous people longed to see what you see but did not see it, and to hear what you hear but did not hear it” (Mt 13:17). In the Eucharist the Church both receives the gift of Jesus Christ and gives grateful thanks to God for such a blessing. This thanksgiving is the only proper response, for through this gift of himself in the celebration of the Eucharist under the appearances of bread and wine Christ gives us the gift of eternal life.
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. . . . Just as the living Father sent me and I have life because of the Father, so also the one who feeds on me will have life because of me. (Jn 6:53-57)
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