SOURCE AND SUMMIT OF THE CHURCH’S LIFE
The Eucharist is “the source and summit of the Christian life” (Lumen Gentium 11)…“For in the blessed Eucharist is contained the whole spiritual good of the Church, name Christ himself, our Pasch” (Presbyterorum Ordinis 5)…. In brief, the Eucharist is the sum and summary of our faith.
We must consider the Eucharist as: thanksgiving and praise to the Father; the sacrificial memorial of Christ and his Body; the presence of Christ by the power of his word and of his Spirit.
Eucharist means first of all “thanksgiving,” a sacrifice of thanksgiving to the Father, a blessing by which the Church expresses her gratitude to God for all his benefits.
The Eucharist is the memorial of Christ’s Passover, a memorial that is not merely a recollection of past events, but the proclamation of the mighty works wrought by God for men which, in the liturgical celebration, become in a certain way present and real. Because it is the memorial of Christ’s Passover, the Eucharist is also a sacrifice.
The sacrifice of Christ and the sacrifice of the Eucharist are one single sacrifice. The Eucharist is also the sacrifice of the Church, united with the offering and intercession of Christ.
Catechism of the Catholic Church, #1324, 1327,1358,
1360, 1361, 1363, 1365, 1367, 1368, 1369