In Leviticus, chapter 9, we read that God commands Moses, as part of the old covenant, or ordain a specialized, professional priesthood to offer sacrifices for the people.  Later, as part of “the new covenant in [his] blood” (Lk 22:20), Jesus establishes a new ordained priesthood for the Church and gives its members the authority and power to offer the Holy Sacrifice of the Mass (see Lk 22:14-20).

All Christians share in a common “holy priesthood” offering “spiritual sacrifices” (1 Pt 2:5) such as prayer, almsgiving (see Heb 13:15-16), and faith in Jesus (see Phil 2:17).  But the special mission that Christ gave his apostles, their successors, and the priests they were to ordain — which includes, among other functions, presiding at the Eucharist and administering the sacrament of Reconciliation — was not to be shared by all of his followers.  “For … all the parts [of Christ’s body] do not have the same function” (Rom 12:4).

The New Testament refers to three types of permanent ordained offices in the Church: bishop (in Greek, episkopos), elder (presbyteros, from which we derive the English words “presbyter” and “priest”), and deacon (diakonos).  The term prebyteros, usually translated “elder”, appears often in Scripture (for example, Acts 15:2-6; 21:18; 1 Pt 5:1; 1 Tm 5:17).  Nearly all Christians accepted this ordained ministry for the first sixteen centuries of the Church’s history, though certain heretical groups, such as the Cathari (who taught Gnostic ideas), rejected it.

Non-Catholic Christians sometimes cite 1 Peter 2:5, 9 and Revelation 1:6 to support their claim that the Church is “a kingdom of priests,” it cannot have a special ministerial priesthood as well.  Nevertheless, in these texts, 1 Peter is quoting — and Revelation is echoing — the words of God to the ancient Hebrews recorded in Exodus 19:6.  If the Lord could refer to that entire nation as priests, even though they had an ordained priesthood, then sure the same is true of the Church.

Related Scripture:

Texts Cited: Lv 9  •  Ex 19:6  •  Lk 22:14-20  •  Acts 15:2-6; 21:18  •  Rom 12:4  •  Phil 2:17  •  1 Tm 5:17  •  Heb 13:15-16  •  1 Pt 2:5, 9; 5:1  •  Rv 1:6
General: Mt 18:18  •  Lk 10:16; 22:19; 24:47  •  Jn 13:20; 15:5; 20:21-23  •  Acts 2:38, 41; 5:2-11; 14:23  •  Rom 10:15  •  1 Cor 4:1; 5:3-13  •  2 Cor 5:18-20  •  Eph 4:11  •  1 Tm 1:18-20; 4:14; 5:23  •  Ti 3:10  •  Jas 5:13-15
Catechism of the Catholic Church: 877  •  1088  •  1142  •  1461  •  1536  •  1539-1553  •  1564-1568  •  1578-1587  •  1591-1592