Roman Missal, Third Edition

The liturgy is the summit toward which the activity of the Church is directed; it is also the font from which all her power flows." It is therefore the privileged place for catechizing the People of God. "Catechesis is intrinsically linked with the whole of liturgical and sacramental activity, for it is in the sacraments, especially in the Eucharist, that Christ Jesus works in fullness for the transformation of men."

Catechism of the Catholic Church, paragraph 1074
 

The Eucharist is "the source and summit of the Christian life." "The other sacraments, and indeed all ecclesiastical ministries and works of the apostolate, are bound up with the Eucharist and are oriented toward it. For in the blessed Eucharist is contained the whole spiritual good of the Church, namely Christ himself, our Pasch."