CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 1187–1191

1187 The liturgy is the work of the whole Christ, head and body. Our high priest celebrates it unceasingly in the heavenly liturgy, with the holy Mother of God, the apostles, all the saints, and the multitude of those who have already entered the kingdom.
1188 In a liturgical celebration, the whole assembly is leitourgos, each member according to his own function. The baptismal priesthood is that of the whole Body of Christ. But some of the faithful are ordained through the sacrament of Holy Orders to represent Christ as head of the Body.
1189 The liturgical celebration involves signs and symbols relating to creation (candles, water, fire), human life (washing, anointing, breaking bread) and the history of salvation (the rites of the Passover). Integrated into the world of faith and taken up by the power of the Holy Spirit, these cosmic elements, human rituals, and gestures of remembrance of God become bearers of the saving and sanctifying action of Christ.
1190 The Liturgy of the Word is an integral part of the celebration. The meaning of the celebration is expressed by the Word of God which is proclaimed and by the response of faith to it.
1191 Song and music are closely connected with the liturgical action. The criteria for their proper use are the beauty expressive of prayer, the unanimous participation of the assembly, and the sacred character of the celebration.