In the liturgy the Church celebrates God’s saving act of redemption in Christ’s Passion, Resurrection, and Ascension. By actively and consciously participating in the liturgy the members fully partake in God’s work of redeeming them and are transformed. It is because of this that the Second Vatican Council stated: “Nevertheless the liturgy is the summit toward which the activity of the Church is directed; at the same time it is the font from which all her power flows.” (Constitution on the Sacred Liturgy, 10)
The whole liturgical life of the Church revolves around the Eucharistic sacrifice and the sacraments. There are seven sacraments in the Church: Baptism, Confirmation or Chrismation, Eucharist, Penance, Anointing of the Sick, Holy Orders, and Matrimony.
Sacraments are "powers that comes forth" from the Body of Christ, which is ever-living and life-giving. They are actions of the Holy Spirit at work in his Body, the Church. They are "the masterworks of God" in the new and everlasting covenant.
Catechism of the Catholic Church 1113 & 1116