“Holy Orders is the sacrament through which the mission entrusted by Christ to his apostles continues to be exercised in the Church until the end of time: thus it is the sacrament of apostolic ministry” (CCC #1536). There are three degrees of this sacrament: deacons, priests, and bishops.

It is important to understand that there is only one Priest, one Priesthood in the Church, namely Jesus Christ. Not only was Jesus the perfect paschal sacrifice, he also offered himself in sacrifice in the most perfect way – through total obedience to God his Father. This makes Jesus the perfect Priest as well as the perfect sacrifice.

In uniting themselves to Christ, the Christian is also participating in Christ Jesus’ priesthood. When we are baptized, we are made “priest, prophet, and king” in Christ. “The faithful exercise their baptismal priesthood through their participation, each according to his own vocation, in Christ’s mission as priest, prophet, and king” (CCC #1546).

The ministerial or hierarchical priesthood, is essentially different from the common priesthood of all the faithful. The common priesthood of the faithful is exercised by the unfolding of the grace of baptism, whereas the men called to serve in the ministerial priesthood receive special graces that are to be used in the service of the common priesthood. “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” (CCC #1547). Through the sacrament of Holy Orders the man is changed in his very being, his essence. He is configured to Christ Jesus.

As was mentioned, there are three degrees of Holy Orders. “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” (CCC #1554).

The fullness of the sacrament of Holy Orders is exercised by Bishops. “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 a wise that bishops, in an eminent and visible manner, take the place of Christ himself, teacher, shepherd, and priest, and act as his representative” (CCC #1558).

Next below the episcopacy, are the priests, who are the co-workers of the bishops. Because the presbyterate is joined to the episcopacy, priests shares in the authority by which Christ builds up and sanctifies and rules his Body. Through the sacrament of Holy Orders, the priest is anointed by the Holy Spirit and receive 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.

The lowest level of Holy Orders (but always the first one received) is that of deacons, who are called “in order to serve.” “At a lower level of the hierarchy are to be found deacons, who receive the imposition of hands ‘not unto the priesthood, but unto the ministry.’” (CCC #1569). Among other things, it is the task of deacons to assist the bishop and priests in the celebration of the divine mysteries, in the proclamation of the Gospel, in the distribution of Holy Communion, in assisting at and blessing marriages, in presiding over funerals, and in dedicating themselves to the various ministries of charity.