Eucharist (Catholic Church)

The Eucharist in the Catholic Church is the celebration of Mass, the eucharistic liturgy. The term Eucharist is also used for the bread and wine when transubstantiated (their substance having been changed), according to Catholic teaching, into the body and blood of Jesus Christ. "At the Last Supper, on the night he was betrayed, our Saviour instituted the Eucharistic sacrifice of his Body and Blood."

Because Christ himself is present in the sacrament of the altar, he is to be honored with the worship of adoration. "To visit the Blessed Sacrament is ... a proof of gratitude, an expression of love, and a duty of adoration toward Christ our Lord."

Blessed Sacrament is a devotional term used in the Roman Catholic Church to refer to the eucharistic species (the Body and Blood of Christ). Consecrated hosts are kept in a tabernacle after Mass, so that the Blessed Sacrament can be brought to the sick and dying outside the time of Mass. This makes possible also the practice of eucharistic adoration.

The Catholic Church sees as the main basis for this belief the words of Jesus himself at his Last Supper: the Synoptic Gospels (Matthew 26-28; Mark 14:22-24; Luke 22:19-20) and Saint Paul's 1 Corinthians 11:23-25 recount that in that context Jesus said of what to all appearances were bread and wine: "This is my body … this is my blood." The Catholic understanding of these words, from the Patristic authors onward, has emphasized their roots in the covenantal history of the Old Testament.

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