The sacrament of the Eucharist is a sacrament instituted by Jesus Christ, in which Jesus Christ Himself, the author of grace, is truly, really, and substantially contained under the species of bread and wine, for the spiritual nourishment of our souls.
“He that eateth my flesh, and drinketh my blood, hath everlasting life: and I will raise him up in the last day. For my flesh is meat indeed: and my blood is drink indeed. He that eateth my flesh, and drinketh my blood, abideth in me, and I in him. As the living Father hath sent me, and I live by the Father; so he that eateth me, the same also shall live by me” (Jn. 55-58).
Jesus Christ instituted this sacrament that He may remain continually present among us and, in return, that He may be loved and honored. He instituted it to be united with us through Holy Communion, to nourish our soul with the heavenly food that enables us to protect and preserve our spiritual life. Lastly, He instituted it to become, at the end of our life, our viaticum for eternity.
“This is the bread which cometh down from Heaven; that if any man eat of it, he may not die.
I am the living bread which came down from Heaven. If any man eat of this bread, he shall live for ever; and the bread that I will give, is my flesh, for the life of the world” (Jn. 6:50-52).
Sacrament and sacrifice
Between the sacrament and the sacrifice of the Eucharist there are the following differences:
The sacrament is produced through the consecration and remains, while the sacrifice consists in the oblation of the divine victim. Thus the Mass is essentially sacrifice, but the divine host contained in the ciborium or carried to a patient is a sacrament and not a sacrifice.
The sacrament is a cause of merit for those who receive the holy Host, and it gives them spiritual advantages, while the sacrifice not only has the effect of merit, but also of satisfaction.