The Eucharist and Christian Initiation
The Eucharist is the final sacrament that completes Christian initiation. Those who have received Baptism, elevating them to the royal priesthood, and Confirmation, which deepens their connection to Christ, participate in the Eucharist with the whole Christian community, joining in the Lord’s sacrifice.

I. The Eucharist – Source and Summit of Ecclesial Life
The Eucharist is the "source and summit of Christian life," as it contains all the spiritual good of the Church, namely Christ. It binds the faithful in unity and communion with God, anticipated in the heavenly liturgy. The Eucharist is the culmination of God's sanctifying action and our worship of Him. It’s the essence of Christian faith and shapes how we think and live.

II. What is the Eucharist Called?
The Eucharist is called by many names, each reflecting different aspects of the sacrament:

• Eucharist: An act of thanksgiving to God.

• The Lord’s Supper: Commemorates the meal before Christ’s Passion and anticipates the heavenly feast.

• The Breaking of Bread: Refers to Jesus’ action of blessing and sharing the bread at the Last Supper.

• Eucharistic Assembly: The gathering of the faithful to celebrate the Eucharist.

• Memorial of the Lord’s Passion and Resurrection: A remembrance of Christ’s death and resurrection.

• The Holy Sacrifice: Represents Christ’s ultimate sacrifice on the cross.

• The Holy and Divine Liturgy: The central act of worship in the Church.

• Holy Communion: Union with Christ’s Body and Blood.

• Holy Mass: Refers to the sending forth of the faithful to fulfill God’s will.

III. The Eucharist in the Economy of Salvation
The bread and wine, at the heart of the Eucharistic celebration, become the Body and Blood of Christ through the words of Christ and the Holy Spirit. These elements symbolize creation’s goodness and express gratitude for God’s gifts. In the Old Covenant, bread and wine were offerings of thanksgiving, but with Christ’s institution of the Eucharist, their meaning is completed. Jesus’ miracles, like the multiplication of loaves and the wedding at Cana, prefigure the abundance and transformative nature of the Eucharist.

The Institution of the Eucharist
At the Last Supper, during the Passover meal, Jesus instituted the Eucharist as a memorial of His death and Resurrection. He commanded His apostles to continue this practice until His return, making them priests of the New Testament.

"Do This in Memory of Me"
Jesus’ command to repeat His actions at the Last Supper is not just to remember Him, but to continue celebrating His life, death, and Resurrection through liturgy. From the early Church, Christians have gathered to "break bread" on Sundays, the day of the Resurrection. This practice remains central to the Church’s life and will continue until the heavenly banquet at the end of time.

IV. The Liturgical Celebration of the Eucharist

The Mass of All Ages From the second century, St. Justin Martyr described the basic structure of the Eucharistic celebration, which has remained the same across different liturgical traditions. Christians gather on Sundays to hear Scripture, offer prayers, share the sign of peace, and then participate in the Eucharist—bread and wine, which become the body and blood of Christ through a prayer of thanksgiving.

The Structure of the Eucharist The Eucharist follows two main parts: the Liturgy of the Word (Scripture readings, homily, and prayers) and the Liturgy of the Eucharist (offering bread and wine, consecration, and communion). Together, they form one unified act of worship, symbolizing the union of God’s Word and Christ's Body.

The Movement of the Celebration Christ is the head of the assembly, presiding over the Eucharist through the priest. The Liturgy of the Word includes Old Testament readings and the Gospels, followed by a homily and intercessions. In the Offertory, bread and wine are presented to the priest as a symbol of the Creator's gifts, which are then transformed into Christ's body and blood during the Eucharistic Prayer.

V. The Sacramental Sacrifice: Thanksgiving, Memorial, and Presence

Thanksgiving to the Father The Eucharist is an act of praise and thanksgiving for God's creation, redemption, and sanctification. The Church offers the sacrifice of praise through Christ, as it recalls God’s goodness and the gifts of salvation.

The Memorial of Christ's Sacrifice The Eucharist is the memorial of Christ’s Passion, death, and resurrection. Through the celebration, Christ’s one sacrifice is made present. The words of institution in the Eucharistic Prayer re-present the sacrifice of the Cross, making it accessible to all generations of Christians.

The Presence of Christ Christ is present in the Eucharist, not only in the Word and in prayer but especially under the forms of bread and wine. Through the conversion of the bread and wine by the Holy Spirit and Christ's words, the real presence of Christ is manifested. This presence is unique and substantial—Christ is fully present in both the bread and the wine, and his presence is constant until the Eucharistic species are consumed.

Worship of the Eucharist Adoration of the Eucharist is an essential part of Catholic practice. The faithful express reverence by bowing, genuflecting, or engaging in silent adoration. The Eucharist is also kept in the tabernacle, where it can be venerated outside Mass and taken to the sick. Christ remains in the Eucharist as a symbol of his love, calling the faithful to a deeper relationship with him through prayer and contemplation.