Sections 
WORDS OF CONSECRATION
If the Eucharistic Prayer is the heart of the Mass, the words of consecration are the heart of the Eucharistic Prayer. The remainder of the Mass is the sacred sign of this sacred moment. 
Since the celebration of the Last Supper, the Church has faithfully maintained Jesus’ commandment: “Do this in memory of me.” Throughout the Eucharistic celebration, the Church makes present that moment, those gestures and words that Jesus realized and pronounced. In that Supper, Christ instituted the sacrifice and paschal invitation, by which the sacrifice of the Cross is continually present in the church when the priest, who represents Christ, the Lord, pronounces “in persona Christi” Jesus’ words. In this moment, those same words that Jesus pronounced, in a special way “are resounded again” by the sacramental re-presentation of Christ in the priest:
“For Christ took the bread and the chalice and gave thanks; he broke the bread and gave it to his disciples, saying, "Take, eat, and drink: this is my Body; this is the cup of my Blood. Do this in memory of me." Accordingly, the Church has arranged the entire celebration of the Liturgy of the Eucharist in parts corresponding to precisely these words and actions of Christ.” (GIRM, 72)
By the ministry of the Catholic priest, it is the same Christ, only Priest of the New Covenant, who pronounces these liturgical words, of infinite doxological and redemptive power. By these words, which at the same time are Christ’s and of His bride the Church, the unique happening of the paschal mystery which occurred many centuries ago, escaping the confines of the special-temporal, where all the human historical occurrences have been confined, it is realized and made present today, under the sacred veils of the liturgy. “Take and eat my body, take and drink my blood”. In the Eucharist, Christians, just like the apostles, participate in the Lord’s Supper, just like the Virgin Mary, St. John and the pious women assisted on Calvary at the sacrifice of the Cross. Mysterium fidei! (cf. J. Ma Iraburu, “Eucharist Synthesis”). 
This is, in effect, the faith of the Church, solemnly proclaimed by Paul VI in his Creed of the People of God (1968, n.24): “We believe that the Mass, celebrated by the priest re-presenting the person of Christ, is really the sacrifice of Calvary made sacramentally present on our altars.”
But we must ask ourselves: What did Jesus want to offer us with those words of the Last Supper: “This is my body”? The word “body” is not indicated in the Bible as a component or part of man that unites to other parts to form a complete man. In the biblical language, and consequently in the language of Jesus and St. Paul, “body” designates the entire man: man in his totality and unity. It designates man in the way he lives his life in a body, in a bodily and mortal condition. St. John, in his Gospel, instead of the word “body”, uses the word “flesh” (“unless you eat of the flesh of the Son of Man…”), and it is clear that the word we find in Chapter 6 of his Gospel, has the same meaning as in the first chapter, where he says, “the Word became flesh,” in other words: man. “Body” indicates all of life. Jesus, when he instituted the Eucharist, has left us the gift of His life, since the first moment of the Incarnation to the last moment, with everything that concretely had filled that life: silence, sweat, fatigue, prayer, struggles, humilliations…
He also says: “This is my blood.” What does He add by His “blood,” if in giving us His body, He has already given us all his life? He adds His death! After having given us his life, he gives us the most precious part, His death. The word “blood” in the Bible, does not indicate a part of his body, in other words, it does not refer to a part of the man. This word rather indicates an occurrence: death. If blood is the essence of life (as Jews thought of it then), His “spilling” of His blood is the concrete symbol of death. “Having loved as His own those who were in the world, he loved them to the extreme” (Jn13:1). The Eucharist is the mystery of the Body and Blood of the Lord, in other words, it is the mystery of the life and death of the Lord.
Each one of us is called to give our body and blood with Jesus in the Mass. With the word “body”, we offer all that is life in our body: time, health, energy, capacity, loves, perhaps only one smile…
With the word “blood,” we express the offering of our death. Not only our definitive death, but everything that anticipates such death: humiliations, failures, sickness, everything that seems repulsive to our nature. St. Paul, in Rom 12:1, exhorts us to offer our “bodies” as a living host, holy and satisfying to God.
When we leave the Eucharistic celebration, we need to work on living what we have finished celebrating united to Christ. We offer our brothers our life, time, energy and attention. In a word, we offer our life. If we say with Christ “take and eat,” we need to allow ourselves to be eaten, especially by those who do not offer us the kindness and consideration we expect. St. Ignatius of Antioch, on the road to martyrdom in Rome, wrote: “I am God’s wheat, and will be milled by the animal’s teeth, with the intent of being presented as holy bread of Christ” (St. Ignatius of Antioch, Letter to the Romans, 4,1). Each one of us can find around us those sharp teeth. We need to learn to be more appreciative towards these brothers, than towards those who praise and approve us. The same St. Ignatius said in another letter: “Those who give me many titles also whip me.” (Letter to the Tarlatans, 4,1).
May we not forget that we have also offered up our “blood,” in other words, our passions, mortifications, sickness, etc. When we are unable to do what we want, that is when we draw nearer to Christ. After His Resurrection, Jesus said to Peter, “When you were younger, you used to dress yourself and go where you wanted; but when you grow old, you will stretch out your hands, and someone else will dress you and lead you where you do not want to go” (Jn 21:18).
Thanks to the Eucharist, no life in the world is useless. Nobody can say: “What is the purpose of my life?,” “Why am I in the world?”. You are in the world for the most sublime purpose: to be a living sacrifice, a living Eucharist with Christ’s Eucharist.
