The Sacrament of Holy Orders is the continuation of Christ's priesthood, which He bestowed upon His Apostles; thus, the Church refers to the Sacrament of Holy Orders as "the sacrament of apostolic ministry.""Ordination" comes from the Latin word ordinatio, which means to incorporate someone into an order. In the Sacrament of Holy Orders, a man or woman is incorporated into the priesthood of Christ, at one of three levels: the episcopate (bishops), the priesthood, or the diaconate (deacons).
From the Catechism 122. What is ordination? Through prayer and the laying on of the bishop’s hands, ordination consecrates, authorizes, and empowers persons called to serve Christ and his Church in the ministry of Word and Sacrament. (1 Timothy 1:5; 5:22; Acts 6:6) 123. What grace does God give in ordination? In ordination, God confirms the gifts and calling of the candidates, conveys the gift of the Holy Spirit for the office and work of bishop, priest or deacon, and sets them apart to act on behalf of the Church and in the name of Christ. 124. What are the three ordained ministries in the Anglican Church? The three orders are bishops, priests, and deacons. 125. What is the work of bishops? The work of bishops is to represent and serve Christ and the Church as chief pastors, to lead in preaching and teaching the faith and in shepherding the faithful, to guard the faith, unity, and discipline of the Church, and to bless, confirm and ordain, thus following in the tradition of the Apostles. (Titus 1:7-9; 1 Timothy 3:1-7; Acts 20:28) 126. What is the work of priests? The work of priests, serving Christ under their bishops, is to nurture congregations through the full ministry of the Word preached and Sacraments rightly administered, and to pronounce absolution and blessing in God’s name. (Titus 1:5; 1 Peter 5:1) 127. What is the work of deacons? The work of deacons, serving Christ under their bishops, is to assist priests in public worship, instruct both young and old in the catechism, and care for those in need. (Acts 6:1-6; 1 Timothy 3:8-13)
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The Priesthood of Christ The priesthood was established by God among the Israelites during their exodus from Egypt. God chose the tribe of Levi as priests for the nation. Their primary duties were the offering of sacrifice and prayer for the people. Christ, in offering Himself up for the sins of all mankind, fulfilled the duties of the Old Testament priesthood once and for all. But just as the Eucharist makes that one sacrifice present to us today, so the New Testament priesthood is a sharing in the eternal priesthood of Christ. While all believers are, in some sense, priests, some are set aside to serve the Church as Christ Himself did. The Ordination of Bishops There is only one Sacrament of Holy Orders, but there are three levels. The first is that which Christ Himself bestowed upon His Apostles: the episcopate. A bishop is a man or woman who is ordained to the episcopate by another bishop (in practice, by several bishops). He stands in a direct, unbroken line from the Apostles, a condition known as "apostolic succession.” Ordination as a bishop confers the grace to sanctify others, as well as the authority to teach the faithful and to bind their consciences. This is a grave responsibility which must be born with much faith and grounding in the teachings of the Church. The Ordination of Priests The second level of the Sacrament of Holy Orders is the priesthood. No bishop can minister to all of the faithful in their diocese, so priests act as "co-workers of the bishops." They exercise their powers lawfully only in communion with their bishop, and so they promise obedience to their bishop (in all things lawful and honest) at the time of their ordination. The chief duties of the priesthood are the preaching of the Gospel, the absolution of sins, and the offering of the Holy Eucharist. The Ordination of Deacons The third level of the Sacrament of Holy Orders is the diaconate. Deacons assist priests and bishops, the preaching of the Gospel, and the care of others is their charism or spiritual gift. There are both ‘transitional deacons’, those who are to be ordained as priests following a period as a deacon; and there are ‘permanent deacons’ who remain in the Order of deacons. All priests and bishops are deacons as well! Eligibility for the Sacrament In the Anglican Communion, and indeed in the diocese of Bathurst, ordination as bishop, priest, and deacon, is open to both men and women. Ordination cannot be demanded, but is a free gift of the Church who may assess candidates by her own criteria. The Form of the Sacrament The essential rite of the sacrament of Holy Orders for all three degrees consists in the bishop's imposition of hands on the head of the ordinand and in the bishop's specific consecratory prayer asking God for the outpouring of the Holy Spirit and his gifts proper to the ministry to which the candidate is being ordained. Other elements of the sacrament, such as holding it in the cathedral (the bishop's own church); holding it during a Eucharist service; and celebrating it on a Sunday are traditional but not essential. The Minister of the Sacrament Because of their role as a successor to the Apostles, who were themselves successors to Christ, the bishop is the proper minister of the sacrament. The grace of sanctifying others that they receive at their own ordination allows them to ordain others. The Effects of the Sacrament The Sacrament of Holy Orders, like the Sacrament of Baptism and the Sacrament of Confirmation, can only be received once for each level of ordination. Once a man or woman has been ordained, they are spiritually changed, which is the origin of the saying, "Once a priest, always a priest." They can be dispensed of their obligations as a priest (or even forbidden to act as a priest); but they remain a priest forever.
Each level of ordination confers special graces, from the ability to preach, granted to deacons; to the ability to act in the person of Christ to offer the Eucharist, granted to priests; to a special grace of strength, granted to bishops, which allows them to teach and lead their flock, even to the point of dying as Christ did.