The Holy Eucharist completes Christian initiation. Those who have been raised to the dignity of the royal priesthood by Baptism and configured more deeply to Christ by confirmation participate with the whole community in the Lord's own sacrifice by means of the Eucharist
(Catechism of the Catholic Church, 1322).
"At the Last Supper, on the night he was betrayed, our savior instituted the Eucharistic sacrifice of his Body and Blood. This he did in order to perpetuate the sacrifice of the cross throughout the ages until he should come again, and so to entrust to his beloved Spouse, the Church, a memorial of his death and resurrection: a sacrament of love, a sign of unity, a bond of charity, a Paschal banquet; in which Christ is consumed, the mind is filled with grace, and a pledge of future glory is given to us."
(Constitution on the Sacred Liturgy, 47; quoted in CCC, 1323)
Who can receive the Eucharist?
GUIDELINES FOR THE RECEPTION OF COMMUNION
As Catcholics, we fully participate in the celebration of the Eucharist when we receive Holy Communion. We are encouraged to receive Communion devoutly an frequently. In order to be properly disposed to receive Communion, participants should not be conscious of grave sin and normally should have fasted for one hour. A person who is conscious of grave sin is not to receive the Body and Blood of the Lord without prior sacramental confession except for a grave reason where there is no opportunity for confession. In this case, the person is to be mindful of the obligation to make an act of perfect contrition, including the intention of confessing as soon as possible (Code of Canon Law, canon 916). A frequent reception of the Sacrament of Penance is encouraged for all.
For Fellow Christians:
We welcome our fellow Christians to this celebration of the Eucharist as our brothers and sisters. We pray that our common baptism and the action of the Holy Spirit in this Eucharist will draw us closer to one another and begin to dispel the sad divisions that separate us. We pray that these will lessen and finally disappear, in keeping with Christ's prayer for us "that they may all be one" (John 17:21). Because Catholics believe that the celebration of the Eucharist is a sign of the reality of the oneness of fait, life, and worship, members of those churches with whom we are not yet fully united are ordinarily not admitted to Holy Communion. Eucharistic sharing inexeptional circumstances by other Christians requires permission according to the directives of the diocesan bishop and the provisions of canon law (canon 844 § 4). Members of the Orthodox Churches, the Assyrian Church of the East, and the Polish National Catholic Church are urged to respect the discipline of their own Churches. According to Roman Catholic discipline, the Code of Canon Law does not object ot the reception of Communion by Christians of these Churches (canon 844 § 3).
For those not receiving Holy Communion:
All who are not receiving Holy Communion are encouraged to express in their hearts a prayerful desire for unity with the Lord Jesus and with one another.
We also welcome to this celebration those who do not share our faith in Jesus Christ. While we cannot admit them to Holy Communion, we ask them to offer thier prayers for the peace and unity of the human family.
United States Catholic Conference of Bishops November 1996 ® All rights reserved.
How often should I receive the Eucharist?
As frequently as possible! Actually, the Church prescribes that Catholics receive the Eucharist at least once per year (during Easter) but recommends that Catholics partake of the sacrament as frequently as possible (not to exceed two times per day). After all, if the Eucharist really is what the Church believes, why wouldn’t a person want to receive Christ daily or at least as often as possible?
What are the effects of receiving the Eucharist?
Just as is the case with all of the sacraments, the Eucharist instills the very life of God into the recipient. In other words, they bring grace to the grace needy. Specifically though, the Church teaches that the effects of the Eucharist are four-fold:
Our relationship (union) with Christ is deepened
The supernatural, divine life, in the recipient is increased, strengthening him/her to live a holy, loving, self-sacrificing Christian life
The recipient is separated from sin (venial sin is forgiven and the recipient is preserved from mortal sin)
The recipient is united more firmly to other members of the Church and as such the Church grows in unity
What is the "Eucharistic fast" and how long is it?
The Eucharistic fast is a one hour fast before receiving Holy Communion to observe a period of reflecting and spiritual hunger for Our Lord. Only medicine and water are allowed before hand, but if one needs to eat for serious medical reason this, for pastoral reasons, is allowed.
CATECHISM OF THE CATHOLIC CHURCH - 1340
" By celebrating the Last Supper with his apostles in the course of the Passover meal, Jesus gave the Jewish Passover its definitive meaning. Jesus' passing over to his father by his death and Resurrection, the new Passover, is anticipated in the Supper and celebrated in the Eucharist, which fulfills the Jewish Passover and anticipates the final Passover of the Church in the glory of the kingdom."
CCC 1340 by USCCB.org
CANON LAW 897 - TITLE III: THE EUCHARIST
"The most venerable sacrament is the blessed Eucharist, in which Christ the Lord himself is contained, offered and received, and by which the Church continually lives and grows. The eucharistic Sacrifice, the memorial of the death and resurrection of the Lord, in which the Sacrifice of the cross is forever perpetuated, is the summit and the source of all worship and Christian life. By means of it the unity of God's people is signified and brought about, and the building up of the body of Christ is perfected. The other sacraments and all the apostolic works of Christ are bound up with, and directed to, the blessed Eucharist. "
CATHOLIC ENCYCLOPEDIA: THE EUCHARIST
"Since Christ is present under the appearances of bread and wine in a sacramental way, the Blessed Eucharist is unquestionably a sacrament of the Church. Indeed, in the Eucharist the definition of a Christian sacrament as "an outward sign of an inward grace instituted by Christ is verified."