We turn to the final sub-section of part II looking at the Eucharist through the ministry of the bishop and priest. First, a reminder of the “public and social” nature of liturgy:
42. The celebration of the eucharist expresses in a special way the public and social nature of the liturgical celebrations of the Church, “which is the sacrament of unity, namely, the holy people united and ordered under their bishops.” [Sacrosanctum Concilium art. 26.]
Then the importance of the bishop, not as a vicar of the pope or of Rome, but as the shepherd responsible for good liturgy within a diocese:
Hence “marked with the fullness of the sacrament of orders, a bishop is the steward of the grace of the supreme priesthood, especially in the eucharist, which he offers or causes to be offered . . . Every lawful celebration of the eucharist is regulated by the bishop, to whom is committed the office of offering the worship of Christian religion to the divine majesty and of administering it in accordance with the Lord’s commandments and the Church’s laws, as further defined by his particular judgment for his diocese.” [Lumen gentium no. 26.] The celebration of the eucharist at which the bishop presides, surrounded by his college of priests and ministers, with the whole people of God actively taking part, is the preeminent manifestation of the hierarchically constituted Church. [See Sacrosanctum Concilium art. 41.]
What of priests?
43. In the celebration of the eucharist, priests also are deputed, by reason of a special sacrament, namely, orders, to fulfill the office proper to them. For they too “as ministers of the sacred, especially in the sacrifice of the Mass, . . . represent the person of Christ in a particular way.” [Presbyterorum ordinis no. 13; see also Lumen gentium no. 28.] Because of the sign value, it is therefore right that they take part in the eucharist by exercising the order proper to them, [See Sacrosanctum Concilium art. 28.] that is, by celebrating or concelebrating the Mass and not simply by receiving communion like the laity.