The sacrament of the Blessed Eucharist is the Body, Blood, Soul and Divinity of Jesus Christ under the appearances, or accidents, of bread and wine. Unlike the other sacraments, it not only bestows grace, but contains the Author of Grace Himself. According to St. Thomas Aquinas (S.T. III, q.65 a. 3, C.), all the other Sacraments point to, or are servants of, the Blessed Eucharist.

The Minister of this sacrament is the Priest or Bishop who consecrates the Blessed Eucharist at Mass. He is therefore the "Minister of Consecration." Upon pronouncing the words "This is my Body," "This is my Blood," the bread and wine become truly the Body and Blood of Christ. These words are the very words of Christ Himself pronounced at the Last Supper:

"Jesus took bread, and blessed, and broke it, and gave it to the disciples and said, Take, eat; this is my body. And he took a cup, and when he had given thanks he gave it to them, saying, Drink of it, all of you; for this is my blood of the covenant, which is poured out for many for the forgiveness of sins" (St. Matt. 26, 26-28).

This mysterious change is called Transubstantiation by the Church (Lateran IV 1215).

The Priest is also normally the "Minister of Distribution," distributing the Eucharistic hosts to the faithful. Where necessary, lay "Extraordinary Ministers of the Eucharist" with due permission and authority may distribute the sacred species.

The Priest celebrating Mass is obliged to receive the Eucharist under the two species of bread and wine. This is in order to properly fulfill the Rite as established by Our Lord. However, it is not obligatory for the laity to receive under both species since Christ's Body, Blood, Soul and Divinity are wholly present under either species. This is insinuated in His words: "he who eats this bread will live forever" (St. John 6, 58).

Any person who has been validly baptized is a fit subject to receive the Eucharist. After reaching the age of reason and being properly instructed in the nature of the Eucharist, one is obliged to receive it at least once a year, at or about Easter time (Lateran IV 1215). Our Lord Himself stated: "unless you eat the flesh of the Son of Man and drink his blood, you have no life in you" (St. John 6, 53).

In preparing for the reception of Holy Eucharist, the candidate must first complete the prescribed fast of at least (traditionaly) 3 hour before-hand. The subject must in good conscience believe that he or she is in a state of grace, free from all mortal sin. For, as St. Paul says: "...Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord...For any one who eats and drinks without discerning the body eats and drinks judgment upon himself" (1 Cor. 11, 27-29). A person in mortal sin must first go to Confession and receive the sacrament of Penance before receiving the Eucharist. Furthermore, we should earnestly strive to free our souls of all venial sin, to increase as much as possible the inflow of grace.

After receiving communion, we should spend time in prayer making acts of faith, adoration and thanksgiving. As St. Peter Julian Eymard has said "the most solemn moment in Christian life is that of thanksgiving after Communion." We should offer ourselves entirely to God and beg His graces for ourselves, others, the Church, and for the dead.

Each occasion a person communicates worthily he or she receives an increase of sanctifying grace, as well as sacramental grace, or claim to actual graces to help us live the life of holiness. Dwelling within us as long as the species of bread and wine remain, Christ's Soul is mysteriously united with our own, breathing into it His own love. United to Christ, we are thereby united to all the faithful: "we who are many are one body, for we all partake of the one bread" (1 Cor. 10, 17).

As food nourishes the body, so the Holy Eucharist nourishes the soul by giving it new energy, fervor and vitality. It can preserve the soul from mortal sin by stifling our carnal appetites, weakening our sensual and worldly desires, and opening our eyes and minds to a love of those things of God, giving us a greater willingness to follow Christ and His Church.

Being a living tabernacle of Christ on earth, the body too is given a special pledge: "he who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day" (St. John 6, 54). It is fitting that the Christian body should not see final corruption, but share with Christ the privilege of a resurrection.

The text of St. John 6, 48-55 in which Our Lord first promised the Holy Eucharist, reads as follows:

"I am the bread of life. Your fathers ate the manna in the wilderness, and they died. This is the bread which comes down from heaven, that a man may eat of it and not die. I am the living bread which came down from heaven; if any one eats of this bread, he will live for ever; and the bread which I shall give for the life of the world is my flesh. The Jews then disputed among themselves, saying, How can this man give us his flesh to eat? So Jesus said to them, Truly, truly, I say to you, unless you eat the flesh of the Son of man and drink his blood, you have no life in you; he who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day. For my flesh is food indeed, and my blood is drink indeed."

The Jews declared "This teaching is difficult, who can accept it?" (v. 60) and "no longer went about with him" (v. 66). Catholics, on the other hand, profess the faith of Simon Peter who answered "Lord, to whom can we go? You have the words of eternal life" (v. 68).