In Brief CCC 1188
© Libreria Editrice Vaticana Source: vatican.va
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.
Read the full chapter 2. The Sacramental Celebration of the Paschal Mystery ¶1135–1209