The Catechism on Priesthood
The one priesthood of Christ
1544 Everything that the priesthood of the Old Covenant prefigured finds its fulfillment in Christ Jesus, the "one mediator between God and men."15 The Christian tradition considers Melchizedek, "priest of God Most High," as a prefiguration of the priesthood of Christ, the unique "high priest after the order of Melchizedek";16 "holy, blameless, unstained,"17 "by a single offering he has perfected for all time those who are sanctified,"18 that is, by the unique sacrifice of the cross.
1545 The redemptive sacrifice of Christ is unique, accomplished once for all; yet it is made present in the Eucharistic sacrifice of the Church. The same is true of the one priesthood of Christ; it is made present through the ministerial priesthood without diminishing the uniqueness of Christ's priesthood: "Only Christ is the true priest, the others being only his ministers."19
Two participations in the one priesthood of Christ
1546 Christ, high priest and unique mediator, has made of the Church "a kingdom, priests for his God and Father."20 The whole community of believers is, as such, priestly. The faithful exercise their baptismal priesthood through their participation, each according to his own vocation, in Christ's mission as priest, prophet, and king. Through the sacraments of Baptism and Confirmation the faithful are "consecrated to be . . . a holy priesthood."21
1547 The ministerial or hierarchical priesthood of bishops and priests, and the common priesthood of all the faithful participate, "each in its own proper way, in the one priesthood of Christ." While being "ordered one to another," they differ essentially.22 In what sense? While the common priesthood of the faithful is exercised by the unfolding of baptismal grace --a life of faith, hope, and charity, a life according to the Spirit--, the ministerial priesthood is at the service of the common priesthood. It is directed at the unfolding of the baptismal grace of all Christians. The ministerial priesthood is a means by which Christ unceasingly builds up and leads his Church. For this reason it is transmitted by its own sacrament, the sacrament of Holy Orders.
In the person of Christ the Head . . .
1548 In the ecclesial service of the ordained minister, it is Christ himself who is present to his Church as Head of his Body, Shepherd of his flock, high priest of the redemptive sacrifice, Teacher of Truth. This is what the Church means by saying that the priest, by virtue of the sacrament of Holy Orders, acts in persona Christi Capitis:23
It is the same priest, Christ Jesus, whose sacred person his minister truly represents. Now the minister, by reason of the sacerdotal consecration which he has received, is truly made like to the high priest and possesses the authority to act in the power and place of the person of Christ himself (virtute ac persona ipsius Christi).24
Christ is the source of all priesthood: the priest of the old law was a figure of Christ, and the priest of the new law acts in the person of Christ.25
1549 Through the ordained ministry, especially that of bishops and priests, the presence of Christ as head of the Church is made visible in the midst of the community of believers.26 In the beautiful expression of St. Ignatius of Antioch, the bishop is typos tou Patros: he is like the living image of God the Father.27
1550 This presence of Christ in the minister is not to be understood as if the latter were preserved from all human weaknesses, the spirit of domination, error, even sin. The power of the Holy Spirit does not guarantee all acts of ministers in the same way. While this guarantee extends to the sacraments, so that even the minister's sin cannot impede the fruit of grace, in many other acts the minister leaves human traces that are not always signs of fidelity to the Gospel and consequently can harm the apostolic fruitfulness of the Church.
1551 This priesthood is ministerial. "That office . . . which the Lord committed to the pastors of his people, is in the strict sense of the term a service."28 It is entirely related to Christ and to men. It depends entirely on Christ and on his unique priesthood; it has been instituted for the good of men and the communion of the Church. The sacrament of Holy Orders communicates a "sacred power" which is none other than that of Christ. The exercise of this authority must therefore be measured against the model of Christ, who by love made himself the least and the servant of all.29 "The Lord said clearly that concern for his flock was proof of love for him."30
. . . "in the name of the whole Church"
1552 The ministerial priesthood has the task not only of representing Christ - Head of the Church - before the assembly of the faithful, but also of acting in the name of the whole Church when presenting to God the prayer of the Church, and above all when offering the Eucharistic sacrifice.31
1553 "In the name of the whole Church" does not mean that priests are the delegates of the community. The prayer and offering of the Church are inseparable from the prayer and offering of Christ, her head; it is always the case that Christ worships in and through his Church. The whole Church, the Body of Christ, prays and offers herself "through him, with him, in him," in the unity of the Holy Spirit, to God the Father. The whole Body, caput et membra, prays and offers itself, and therefore those who in the Body are especially his ministers are called ministers not only of Christ, but also of the Church. It is because the ministerial priesthood represents Christ that it can represent the Church.
The ordination of priests - co-workers of the bishops
1562 "Christ, whom the Father hallowed and sent into the world, has, through his apostles, made their successors, the bishops namely, sharers in his consecration and mission; and these, in their turn, duly entrusted in varying degrees various members of the Church with the office of their ministry."43 "The function of the bishops' ministry was handed over in a subordinate degree to priests so that they might be appointed in the order of the priesthood and be co-workers of the episcopal order for the proper fulfillment of the apostolic mission that had been entrusted to it by Christ."44
1563 "Because it is joined with the episcopal order the office of priests shares in the authority by which Christ himself builds up and sanctifies and rules his Body. Hence the priesthood of priests, while presupposing the sacraments of initiation, is nevertheless conferred by its own particular sacrament. Through that sacrament priests by the anointing of the Holy Spirit are signed with a special character and so are configured to Christ the priest in such a way that they are able to act in the person of Christ the head."45
1564 "Whilst not having the supreme degree of the pontifical office, and notwithstanding the fact that they depend on the bishops in the exercise of their own proper power, the priests are for all that associated with them by reason of their sacerdotal dignity; and in virtue of the sacrament of Holy Orders, after the image of Christ, the supreme and eternal priest, they are consecrated in order to preach the Gospel and shepherd the faithful as well as to celebrate divine worship as true priests of the New Testament."46
1565 Through the sacrament of Holy Orders priests share in the universal dimensions of the mission that Christ entrusted to the apostles. The spiritual gift they have received in ordination prepares them, not for a limited and restricted mission, "but for the fullest, in fact the universal mission of salvation 'to the end of the earth,"'47 "prepared in spirit to preach the Gospel everywhere."48
1566 "It is in the Eucharistic cult or in the Eucharistic assembly of the faithful (synaxis) that they exercise in a supreme degree their sacred office; there, acting in the person of Christ and proclaiming his mystery, they unite the votive offerings of the faithful to the sacrifice of Christ their head, and in the sacrifice of the Mass they make present again and apply, until the coming of the Lord, the unique sacrifice of the New Testament, that namely of Christ offering himself once for all a spotless victim to the Father."49 From this unique sacrifice their whole priestly ministry draws its strength.50
1567 "The priests, prudent cooperators of the episcopal college and its support and instrument, called to the service of the People of God, constitute, together with their bishop, a unique sacerdotal college (presbyterium) dedicated, it is, true to a variety of distinct duties. In each local assembly of the faithful they represent, in a certain sense, the bishop, with whom they are associated in all trust and generosity; in part they take upon themselves his duties and solicitude and in their daily toils discharge them."51 priests can exercise their ministry only in dependence on the bishop and in communion with him. The promise of obedience they make to the bishop at the moment of ordination and the kiss of peace from him at the end of the ordination liturgy mean that the bishop considers them his co-workers, his sons, his brothers and his friends, and that they in return owe him love and obedience.
1568 "All priests, who are constituted in the order of priesthood by the sacrament of Order, are bound together by an intimate sacramental brotherhood, but in a special way they form one priestly body in the diocese to which they are attached under their own bishop. . . ."52 The unity of the presbyterium finds liturgical expression in the custom of the presbyters' imposing hands, after the bishop, during the Ate of ordination.
15 2 Tim 2:5.
16 Heb 5:10; cf. 6:20; Gen 14:18.
17 Heb 7:26.
18 Heb 10:14.
19 St. Thomas Aquinas, Hebr. 8,4.
20 Rev 1:6; cf. Rev 5:9-10; 1 Pet 2:5,9.
21 LG 10 § 1.
22 LG 10 § 2.
23 Cf. LG 10; 28; SC 33; CD 11; PO 2; 6.
24 Pius XII, encyclical, Mediator Dei: AAS, 39 (1947) 548.
25 St. Thomas Aquinas, STh III,22,4c.
26 Cf. LG 21.
27 St. Ignatius of Antioch, Ad Trall. 3,1:SCh 10,96; cf. Ad Magn. 6,1:SCh 10,82-84.
28 LG 24.
29 Cf. Mk 10:43-45; 1 Pet 5:3.
30 St. John Chrysostom, De sac. 2, 4:PG 48, 636; cf. Jn 21:15-17.
31 Cf. SC 33N; LG 10.
43 LG 28; cf. Jn 10:36.
44 PO 2 § 2.
45 PO 2.
46 LG 28 cf. Heb 5:1-10; 7:24; 9:11-28; Innocent I, Epist. ad Decentium:PL 20,554A; St. Gregory of Nazianzus, Oratio 2,22:PG 35,432B.
47 PO 10; OT 20; cf. Acts 1:8.
48 OT 20.
49 LG 28; cf. 1 Cor 11:26.
50 Cf. PO 2.
51 LG 28 § 2.
52 PO 8.