The word “liturgy” comes from a Greek term meaning “public work or work done on behalf of the people.” Liturgy always referred to an organized community.
A work, then, done by an individual or a group was a liturgy on behalf of the larger community. All the worshipers are expected to participate actively in each liturgy, for this is holy “work,” not entertainment or a spectator event.
Every liturgical celebration is an action of Christ the High Priest and of his Mystical Body, which is the Church. It therefore requires the participation of the People of God in the work of God.
Liturgy is centered on the Holy Trinity. At every liturgy the action of worship is directed to the Father, from whom all blessings come, through the Son in the unity of the Holy Spirit. We praise the Father who first called us to be his people by sending us his Son as our Redeemer and giving us the Holy Spirit so that we can continue to gather, to remember what God has done for us, and to share in the blessings of salvation.
Through the liturgical celebrations of the Church, we participate in the Paschal Mystery of Christ, that is, his passing through death from this life into eternal glory, just as God enabled the people of ancient Israel to pass from slavery to freedom through the events narrated in the Book of Exodus.
The liturgies of the Church also help to teach us about Jesus Christ and the meaning of the mysteries we are celebrating. A mystery is a reality that is both visible and hidden.
Jesus Christ’s death and Resurrection become present to us and effective for us in the liturgical life of the Church. His death and Resurrection are hidden now in the eternity of God, but as Risen Lord and Head of the Church, Jesus Christ calls us to share in them through the liturgy of the Church, that is, by the visible gathering of the community for worship and remembrance of what God has done for us. It is the Holy Spirit, the source of the Church’s life, who draws us together through liturgical actions, the chief of which are the Sacraments.
The term liturgy itself has a broader application than that of Sacrament, for it embraces all the official public prayer life of the Church, while the term Sacrament refers to a particular celebration of Christ’s salvific work. (9:43)