The Sacrament of the Holy Eucharist (Holy Communion)
Short Introduction
The Holy Eucharist is the sacrament in which, under the appearances of bread and wine, Our Lord
Jesus Christ is truly, really, and substantially present — Body, Blood, Soul, and Divinity — to be
received as the food of our souls. Christ instituted this sacrament at the Last Supper when He took
bread and wine, blessed them, and said, “This is My Body… This is My Blood,” commanding His
Apostles, “Do this in commemoration of Me” (Luke 22:19). It is at once a sacrament, a sacrifice,
and the true center of Catholic worship.
Full Explanation
What the Holy Eucharist Is
The Catechism teaches that the Holy Eucharist is the sacrament and the sacrifice in which Christ is
contained, offered, and received under the appearances of bread and wine. Unlike the other sacra-
ments, the Eucharist is not merely a sign that confers grace, but contains within itself the very
Author of grace, Jesus Christ Himself. The Catechism insists repeatedly that after the Consecra-
tion, the substance of bread and wine no longer remains at all — only the appearances (accidents)
of bread and wine remain, while the whole Christ is present under each. This change of the entire
substance of bread into the Body of Christ, and of wine into His Blood, is called Transubstantia-
tion, a term solemnly defined by the Fourth Lateran Council (1215) and reaffirmed by the Council
of Trent against the errors of the Protestant reformers.
Matter and Form
The Catechism explains that the matter of this sacrament is wheaten bread and grape wine. The
form consists of the words of Consecration spoken by the priest in the person of Christ: “This is
My Body” and “This is My Blood… which shall be shed for you and for many unto the remission
of sins.” The ordinary minister who can consecrate the Eucharist is a validly ordained priest or
bishop alone; no one else, of whatever dignity, can effect this consecration.
The Real Presence
St. Thomas Aquinas, whose Eucharistic hymns (such as the Tantum Ergo and Pange Lingua) remain
part of the Church’s devotional treasury, taught that Christ is present whole and entire under each
species and under every part of each species, so that the smallest particle of the Host or drop from
the chalice contains the whole Christ. This presence continues as long as the appearances of bread
and wine remain, which is why the Blessed Sacrament reserved in the tabernacle is adored as truly
containing Our Lord, and why the faithful genuflect before it.
The Holy Mass as Sacrifice
Traditional theology, following the Council of Trent, teaches that the Eucharist is not only a
sacrament to be received but the unbloody renewal of the Sacrifice of Calvary, offered under the
appearances of bread and wine by the priest acting in the person of Christ. The Mass applies the
fruits of Christ’s one sacrifice on the Cross to the living and the dead, and is offered for four ends
traditionally enumerated by the manuals: adoration, thanksgiving, satisfaction for sin, and petition
(impetration).
The Effects of Holy Communion
According to The Catechism, the worthy reception of Holy Communion:
- Increases sanctifying grace in the soul, uniting the communicant intimately with Christ.
- Preserves and strengthens the life of grace received in Baptism.
- Lessens concupiscence — the inclination toward sin — and helps the soul resist temptation.
- Remits venial sin and helps preserve one from mortal sin.
- Is a pledge of eternal life and of the future resurrection of the body, since Christ promised,
“He that eateth this bread shall live for ever” (John 6:59).
Necessary Dispositions
The old catechisms are firm that no one in the state of mortal sin may receive Holy Communion;
such a person must first go to Confession, since to receive unworthily is to commit the grave sin
of sacrilege, as St. Paul warns: “Whosoever shall eat this bread, or drink the chalice of the Lord
unworthily, shall be guilty of the body and of the blood of the Lord” (1 Corinthians 11:27). The
faithful were traditionally also required to observe the Eucharistic fast (abstaining from food and
drink, with the exception of water, from midnight before receiving, per the discipline of the period)
as a mark of reverence for the sacrament.
The Precept of Easter Communion
The 1917 Code of Canon Law bound all the faithful who have reached the age of reason to receive
Holy Communion at least once a year, during the Easter season, following the ancient precept of
the Church, in addition to receiving it worthily whenever in danger of death (the Viaticum).
Preparing to Receive Holy Communion
As with Baptism and Confession, the reception of the Holy Eucharist carries clear responsibilities
for the communicant and, in the case of children, for parents preparing them for First Communion:
- Be in the state of grace. No one conscious of mortal sin may approach the altar rail
without having first made a sacramental confession. - Observe the Eucharistic fast. The communicant must observe whatever fast is prescribed
by the Church at the time as a sign of reverence and self-denial before receiving. - Have the right intention and reverence. Communion should be received with faith in
the Real Presence, humility, and devout attention, not out of mere routine or human respect. - Give thanks after Communion. The old manuals of piety strongly recommend spend-
ing time in thanksgiving after Mass, since the Real Presence of Christ remains within the
communicant for a time after reception.
- Parents must prepare children carefully for First Communion. Parents and god-
parents share responsibility for ensuring a child understands, before receiving, the difference
between ordinary bread and the Body of Christ, and can distinguish right from wrong suf-
ficiently to examine their conscience — the traditional standard for reaching the “age of
discretion.”
Sources referenced: The Catechism; the decrees of the Council of Trent on the Holy Eucharist; the
canons of the Fourth Lateran Council; the 1917 Code of Canon Law; St. Thomas Aquinas, Summa
Theologica and Eucharistic hymns.