Catholic liturgy

The Catholic Church is fundamentally liturgical and sacramental in its public life of worship.

As explained in greater detail in the Catechism of the Catholic Church and its shorter Compendium, the liturgy is something that "the whole Christ", Head and Body, celebrates — Christ, the one High Priest, together with his Body, the Church in heaven and on earth. Involved in the heavenly liturgy are the angels and the saints of the Old Covenant and the New Covenant, in particular Mary, the Mother of God, the Apostles, the Martyrs and "a great multitude, which no man could number, out of every nation and of all tribes and peoples and tongues" (Revelation 7:9). The Church on earth, "a royal priesthood" (1 Peter 2:9), celebrates the liturgy in union with these: the baptized offering themselves as a spiritual sacrifice, the ordained ministers celebrating at the service of all the members of the Church in accordance with the order received, and bishops and priests acting in the person of Christ.

The Catholic liturgy uses signs and symbols whose significance, based on nature or culture, has been made more precise through Old Testament events and has been fully revealed in the person and life of Christ. Some of these signs and symbols come from the world of creation (light, water, fire, bread, wine, oil), others from life in society (washing, anointing, breaking bread), others from Old Testament sacred history (the Passover rite, sacrifices, laying on of hands, consecrating persons and objects).

These signs are closely linked with words. Though in a sense the signs speak for themselves, they need to be accompanied and vivified by the spoken word. Taken together, word and action indicate what the rite signifies and affects.

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