Ordination

Ordination is the process by which individuals are consecrated, that is, set apart and elevated from the laity class to the clergy, who are thus then authorized (usually by the denominational hierarchy composed of other clergy) to perform various religious rites and ceremonies. The process and ceremonies of ordination may vary by religion and denomination. One who is in preparation for, or who is undergoing, the process of ordination is sometimes called an ordinand. The liturgy used at an ordination is commonly found in a book known as an Ordinal which provides the ordo (ritual and rubrics) for celebrations.

In Catholicism and Orthodoxy, ordination is one of the seven sacraments, variously called holy orders or cheirotonia ("Laying on of Hands").

Apostolic succession is considered an essential and necessary concept for ordination in the Catholic, Orthodox, High Church Lutheran, Moravian, and Anglican traditions, with the belief that all ordained clergy are ordained by bishops who were ordained by other bishops tracing back to bishops ordained by the Apostles who were ordained by Christ, the great High Priest (Hebrews 7:26, Hebrews 8:2), who conferred his priesthood upon his Apostles (John 20:21–23, Matthew 28:19–20, Mark 16:15–18, and Acts 2:33).

There are three ordinations in Holy Orders: deacon, presbyter, and bishop. Both bishops and presbyters are priests and have authority to celebrate the Eucharist. In common use, however, the term priest, when unqualified, refers to the order of presbyter, whereas presbyter is mainly used in rites of ordination and other places where a technical and precise term is required.^{[citation needed]}

Ordination of a bishop is performed by several bishops; ordination of a priest or deacon is performed by a single bishop. The ordination of a new bishop is also called a consecration. Many ancient sources specify that at least three bishops are necessary to consecrate another, e.g., the 13th Canon of the Council of Carthage (AD 394) states, "A bishop should not be ordained except by many bishops, but if there should be necessity he may be ordained by three," and the first of "The Canons of the Holy and Altogether August Apostles" states, "Let a bishop be ordained by two or three bishops," while the second canon thereof states, "Let a presbyter, deacon, and the rest of the clergy, be ordained by one bishop"; the latter canons, whatever their origin, were imposed on the universal church by the Seventh Ecumenical Council, the Second Council of Nicaea, in its first canon.

The Catholic Church teaches that one bishop is sufficient to consecrate a new bishop validly (that is, for an episcopal ordination actually to take place). In most Christian denominations that retain the practice of ordination, only an already ordained (consecrated) bishop or the equivalent may ordain bishops, priests, and deacons. However, Canon Law requires that bishops always be consecrated with the mandate (approval) of the Pope, as the guarantor of the Church's unity. Moreover, at least three bishops are to perform the consecration, although the Apostolic See may dispense from this requirement in extraordinary circumstances (for example, in missionary settings or times of persecution).

In the Catholic Church, those deacons destined to be ordained priests are often termed transitional deacons; those deacons who are married before being ordained, as well as any unmarried deacons who chose not to be ordained priests, are called permanent deacons. Those married deacons who become widowers have the possibility of seeking ordination to the priesthood in exceptional cases.

While some Eastern churches have in the past recognized Anglican ordinations as valid, the current Anglican practice, in many provinces, of ordaining women to the priesthood—and, in some cases, to the episcopate—has caused the Orthodox generally to question earlier declarations of validity and hopes for union. Anglicanism recognizes Catholic and Orthodox ordinations; hence, clergy converting to Anglicanism are not "re-ordained". In 1896, Pope Leo XIII issued the papal bull Apostolicae Curae, which declared Anglican orders "absolutely null and utterly void." While the Vatican has not officially retracted the statement, Roman Catholic actions after the issuance of the bull imply varying positions on the matter. In modern times, the Pope has on several occasions gifted to the Archbishop of Canterbury signs of ecclesiastical office, including a crozier, an episcopal ring, and a Eucharistic chalice, signaling a softening on the Roman view of Anglican orders. In addition, under Pope Francis' tenure, an Anglican bishop was allowed to celebrate mass on the altar of the Archbasilica of Saint John Lateran, the seat of the Pope's own bishopric.