Today’s Catechism sections discuss episcopal ordination. Supporting material comes from the Dogmatic Constitution, “Lumen Gentium”.

III. The Three Degrees of the Sacrament of Holy Orders

1554 "The divinely instituted ecclesiastical ministry is exercised in different degrees by those who even from ancient times have been called bishops, priests, and deacons."32 Catholic doctrine, expressed in the liturgy, the Magisterium, and the constant practice of the Church, recognizes that there are two degrees of ministerial participation in the priesthood of Christ: the episcopacy and the presbyterate. The diaconate is intended to help and serve them. For this reason the term sacerdos in current usage denotes bishops and priests but not deacons. Yet Catholic doctrine teaches that the degrees of priestly participation (episcopate and presbyterate) and the degree of service (diaconate) are all three conferred by a sacramental act called "ordination," that is, by the sacrament of Holy Orders:

Let everyone revere the deacons as Jesus Christ, the bishop as the image of the Father, and the presbyters as the senate of God and the assembly of the apostles. For without them one cannot speak of the Church.33

Episcopal ordination - fullness of the sacrament of Holy Orders

1555 "Amongst those various offices which have been exercised in the Church from the earliest times the chief place, according to the witness of tradition, is held by the function of those who, through their appointment to the dignity and responsibility of bishop, and in virtue consequently of the unbroken succession going back to the beginning, are regarded as transmitters of the apostolic line."34

1556 To fulfil their exalted mission, "the apostles were endowed by Christ with a special outpouring of the Holy Spirit coming upon them, and by the imposition of hands they passed on to their auxiliaries the gift of the Spirit, which is transmitted down to our day through episcopal consecration."35

1557 The Second Vatican Council "teaches . . . that the fullness of the sacrament of Holy Orders is conferred by episcopal consecration, that fullness namely which, both in the liturgical tradition of the Church and the language of the Fathers of the Church, is called the high priesthood, the acme (summa) of the sacred ministry."36

1558 "Episcopal consecration confers, together with the office of sanctifying, also the offices of teaching and ruling.... In fact ... by the imposition of hands and through the words of the consecration, the grace of the Holy Spirit is given, and a sacred character is impressed in such wise that bishops, in an eminent and visible manner, take the place of Christ himself, teacher, shepherd, and priest, and act as his representative (in Eius persona agant)."37 "By virtue, therefore, of the Holy Spirit who has been given to them, bishops have been constituted true and authentic teachers of the faith and have been made pontiffs and pastors."38

1559 "One is constituted a member of the episcopal body in virtue of the sacramental consecration and by the hierarchical communion with the head and members of the college."39 The character and collegial nature of the episcopal order are evidenced among other ways by the Church's ancient practice which calls for several bishops to participate in the consecration of a new bishop.40 In our day, the lawful ordination of a bishop requires a special intervention of the Bishop of Rome, because he is the supreme visible bond of the communion of the particular Churches in the one Church and the guarantor of their freedom.

1560 As Christ's vicar, each bishop has the pastoral care of the particular Church entrusted to him, but at the same time he bears collegially with all his brothers in the episcopacy the solicitude for all the Churches: "Though each bishop is the lawful pastor only of the portion of the flock entrusted to his care, as a legitimate successor of the apostles he is, by divine institution and precept, responsible with the other bishops for the apostolic mission of the Church."41

1561 The above considerations explain why the Eucharist celebrated by the bishop has a quite special significance as an expression of the Church gathered around the altar, with the one who represents Christ, the Good Shepherd and Head of his Church, presiding.42

The Dogmatic Constitution, “Lumen Gentium” discusses the role of the Bishops in the Church.

21. In the bishops, therefore, for whom priests are assistants, Our Lord Jesus Christ, the Supreme High Priest, is present in the midst of those who believe. For sitting at the right hand of God the Father, He is not absent from the gathering of His high priests,(17*) but above all through their excellent service He is preaching the word of God to all nations, and constantly administering the sacraments of faith to those who believe, by their paternal functioning.(150) He incorporates new members in His Body by a heavenly regeneration, and finally by their wisdom and prudence He directs and guides the People of the New Testament in their pilgrimage toward eternal happiness. These pastors, chosen to shepherd the Lord's flock of the elect, are servants of Christ and stewards of the mysteries of God,(151) to whom has been assigned the bearing of witness to the Gospel of the grace of God,(152) and the ministration of the Spirit and of justice in glory.(153)

For the discharging of such great duties, the apostles were enriched by Christ with a special outpouring of the Holy Spirit coming upon them,(154) and they passed on this spiritual gift to their helpers by the imposition of hands,(155) and it has been transmitted down to us in Episcopal consecration.(18*) And the Sacred Council teaches that by Episcopal consecration the fullness of the sacrament of Orders is conferred, that fullness of power, namely, which both in the Church's liturgical practice and in the language of the Fathers of the Church is called the high priesthood, the supreme power of the sacred ministry.(19*) But Episcopal consecration, together with the office of sanctifying, also confers the office of teaching and of governing, which, however, of its very nature, can be exercised only in hierarchical communion with the head and the members of the college. For from the tradition, which is expressed especially in liturgical rites and in the practice of both the Church of the East and of the West, it is clear that, by means of the imposition of hands and the words of consecration, the grace of the Holy Spirit is so conferred,(20*) and the sacred character so impressed,(21*) that bishops in an eminent and visible way sustain the roles of Christ Himself as Teacher, Shepherd and High Priest, and that they act in His person.(22*) Therefore it pertains to the bishops to admit newly elected members into the Episcopal body by means of the sacrament of Orders.

Footnotes

32 LG 28.
33 St. Ignatius of Antioch, Ad Trall. 3,1: SCh 10, 96.
34 LG 20.
35 LG 21; Cf. ⇒ Acts 1:8; ⇒ 24; ⇒ Jn 20:22-23; ⇒ 1 Tim 4:14; ⇒ 2 Tim 1:6-7.
36 LG 21 # 2.
37 LG 21.
38 CD 2 # 2.
39 LG 22.
40 Cf. LG 22.
41 Pius XII, Fidei donum: AAS 49 (1957) 237; cf. LG 23; CD 4; 36; 37; AG 5; 6; 38.
42 Cf. SC 41; LG 26.