Orthodoxy recognizes at least seven Mysteries, or "sacraments": Baptism, chrismation, communion, confession, anointing of the sick, marriage, and holy orders. However nothing formally limits the number of sacraments. Orthodoxy does not emphasize a distinction between these sacraments and such acts as the blessing of water on the feast of Theophany, or the burial service, or the service for the tonsuring of a monk – services that in the West are called sacramentalia. The underlying sacramental theology of the Orthodox Church is based, however, on the understanding that the divine life encountered in the Church is itself the unique mysterion in which the grace of God is communicated, and of which the various sacraments are the normal expressions.

In the West, since the Scholastic period (Middle Ages) and, especially, since the Roman Catholic "Counter-Reformation" (16th century), much emphasis has been placed on the vicarious juridical power of priests to administer the sacraments validly. Orthodoxy, however, sees each sacramental act as a prayer of the entire ecclesiastical community, led by the bishop or his representative the priest, and also as a response by God, based upon Christ’s promise to send the Holy Spirit upon the Church. These two aspects of the sacrament exclude both magic and legalism: they imply that the Holy Spirit is given to free men, and they call for man’s free response. In the mysterion of the Church, man’s participation in God becomes effective through cooperation or synergy; to make this participation possible is the goal of Christ’s incarnation.

Baptism and confirmation

Baptism is normally performed by triple immersion as an initiation into the death and Resurrection of Christ. It is immediately followed by chrismation, ni which the newly-baptized Christian is anointed with oil to receive "the seal of the gift of the Holy Spirit". Baptized and chrismated children are admitted immediately to Holy Communion. By admitting newly-baptized children to Communion, the Orthodox Christian tradition maintains the positive meaning of Baptism as the beginning of a new life nourished by the Eucharist.

The Eucharist

In the East there never has been much speculation about the precise nature of the eucharistic mystery. The Liturgy includes the "words of institution" ("This is My Body… This is My Blood"), however the culminating point of the prayer is not only in the remembrance of Christ’s act, but in the invocation of the Holy Spirit which immediately follows: "Send down Thy Holy Spirit upon us and upon the Gifts here spread forth, and make this bread to be the precious Body of Thy Christ." Thus, the central mystery of Christianity is performed by prayer, through an invocation of the Spirit. The nature of the mystery that occurs in the bread and wine is simply signified by the term metabole ("change"). The western term transubstantiation is not commonly used, as it represents a development in medieval western philosophy with no counterpart in Orthodoxy.

Confession

Confession in the early Church was a solemn and public act of reconciliation, through which an excommunicated sinner was readmitted into Church membership. Historically it has developed into a private act of confession through which every Christian’s membership in the Church is periodically renewed. Confession, in Orthodox practice, is understood as a form of spiritual healing rather than as a tribunal. The relative lack of legalism reflects the Eastern patristic approach to sin as an internal passion and as an enslavement. The external sinful acts – which alone can be legally tried – are manifestations of man’s spiritual illness.

Anointing of the sick

Anointing of the sick is a form of healing by prayer. In the Greek tradition it is performed annually in Church for the benefit of the entire congregation on the evening of Holy Wednesday.

Marriage

Marriage is celebrated through a service of crowning, performed with great joy and ceremony, and signifying a union which sacramentally participates in the Kingdom of God. Orthodox theology of marriage insists on its sacramental reality rather than its legal status. Thus, in cases of either widowhood or divorce, second marriages are celebrated, through a subdued penitential rite.

Holy Orders

There are three major orders of the clergy: the episcopate (bishops), the presbytery (priests), and the diaconate (deacons); as well as minor orders: subdeacons and readers. All ordinations are performed by a bishop during the Divine Liturgy. The consecration of a bishop requires the participation of at least two or three bishops, following election by a canonical synod.

The Bishop. The Orthodox understanding of the Church is based on the principle, attested in the canons and in early Christian tradition, that each local community of Christians, gathered around its bishop and celebrating the Eucharist, is the local realization of the whole body of Christ. "Where Christ is, there is the catholic Church," wrote Saint Ignatius of Antioch (c. 100AD). Modern Orthodox theology also emphasizes that the office of the bishop is the highest among the sacramental ministries, and that there is thus no divinely established authority over that of the bishop in his own community, or diocese. Neither the local Churches nor the bishops, however, can or should live in isolation. The wholeness of Church life, realized in each local community, is one with that of the other local Churches in the present and in the past. This identity and continuity is manifested in the act of the ordination of bishops, an act that requires the presence of several other bishops in order to constitute a conciliar act and to witness to the continuity of apostolic succession and tradition.

The bishop is primarily the guardian of the faith and, as such, the center of the sacramental life of the community. The Orthodox Church maintains the doctrine of apostolic succession – that is, that the ministry of the bishop is necessarily in direct continuity with that of the Apostles of Jesus. However Orthodox tradition, as expressed especially in its medieval opposition to the Roman papacy, distinguishes the office of the "Apostle" from that of the bishop, in that the first is viewed as a universal witness to Jesus Christ and His Resurrection, while the latter is understood in terms of the pastoral and sacramental responsibility for a local community, or Church. The continuity between the apostles and bishops is a continuity in faith rather than in function.

No bishop can be consecrated or exercise his ministry without being in unity with his colleagues – that is, without being a member of an episcopal council, or synod. After the Council of Nicaea (325AD), whose canons are still normative in the Orthodox Church, each province of the Roman Empire had its own synod of bishops that acted as a fully independent unit for the consecration of new bishops and also as a high ecclesiastical tribunal. In the contemporary Orthodox Church these functions are fulfilled by the synod of each autocephalous Church. In the early Church the bishop of the provincial capital acted as chairman of the synod and was generally called metropolitan, archbishop, or patriarch.

The Priest. In Saint Paul’s writings, about the middle of the first century, the roles of bishop (episkopos, overseer) and elder (presbyteros) are essentially interchangeable. Yet shortly after the New Testament period, with the death of the Apostles, there was a differentiation in the usage of the synonymous terms, giving rise to the appearance of two distinct offices of bishop and presbyter. As the number of Christian communities multiplied so that the apostles had to ordain bishops in every city, the number of Christians in each city grew so that a city’s bishop began to function as the president of the council of presbyters. He came to be distinguished both in honor and in authority from the presbyters, who derived their authority by delegation from the bishop. The distinction between presbyter and bishop is already assumed by the end of the Apostolic period, as is seen in the writings of Saint Ignatius, who uses the terms consistently and clearly to refer to two different offices.

Through the sacrament of ordination to the priesthood, an additional measure of grace is granted to empower a man in the preaching of the Gospel through his words and actions and the administration of the mysteries of the Church as a means of grace for himself, and more especially for others. This strengthening is accomplished through the descent of the Holy Spirit upon the ordinand at the bishop’s laying on of his hands. Ordination to the priesthood is the sacrament which enables the rites and common prayer of the Church. Today the normal pastoral functions in the Church are carried out by priests, who shepherd local parishes on behalf of the bishop. The parish priest is "spiritual father" to those in his care, but the priest is not an independent minister; he serves entirely with the blessing of the bishop. Orthodox priests and deacons are usually married men, although they may not marry after ordination.

The Deacon. The deacon ministers to the priest and bishop in the divine services and assists in the celebration of the mysteries of the Church. A deacon may not, however, celebrate the mysteries by himself. With the blessing of the presiding priest or bishop, the deacon leads the people in the collective prayers and reads from the Holy Scriptures during the divine services.

Monasticism. Monks and nuns are not generally ordained clergy, though some monks are ordained as deacons or priests. The tradition of monasticism goes back to the third and fourth centuries of the Christian Era. From its beginning monasticism was a movement seeking the experience of God in a life of permanent prayer. This character has remained its essential feature throughout the centuries. Orthodoxy never experienced the development of religious orders pursuing particular missionary or educational goals and organized on a universal scale, as did western Christianity.

Concern for prayer, as the central and principal function of monasticism, does not mean that the Orthodox monastic movement is of a single uniform character. Hesychastic (solitary) monasticism, emphasizing the personal and individual practice of prayer and asceticism in pursuit of inner silence, has always coexisted with cenobitic (communal) monastic life, in which prayer was primarily liturgical and corporate. The two forms of monasticism originated in the Egyptian deserts and have coexisted throughout the Christian world to this day