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.

-Mysterium Fidei 72, Canon 897

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.

-Canon 897