Following the example of the Old Testament Church, in which there were a high priest, priests, and Levites, the holy Apostles also instituted in the New Testament Christian Church the priesthood: bishops, priests, and deacons. They are all called members of the clergy because by means of the Mystery of the priesthood they receive the Grace of the Holy Spirit for sacred service in the Church of Christ: enabling them to celebrate the divine services; teach the laity the Christian faith and holy life; and direct ecclesiastical affairs.
The bishops comprise the highest rank in the Church, and therefore receive the highest degree of Grace. Bishops are also called hierarchs, or leaders of the priests. They may celebrate all the Mysteries and all ecclesiastical services. Bishops have the right not only to serve the usual Liturgy, but they alone may consecrate others into the priesthood, as well as consecrate Holy Chrism and the Antimensis (a piece of cloth that is placed under the altar table). In their degree of priesthood they are equal, though the senior and most deserving of the bishops are termed archbishops, while the bishops whose sees are centered in major cities are termed metropolitans, after the Greek word for a large city, "metropolis." The bishops of the ancient major cities of the Roman Empire, Jerusalem, Constantinople, Rome, Alexandria and Antioch, are called patriarchs. A bishop sometimes is given another bishop, called a vicar or auxiliary bishop, to assist him in his duties.
Around the shoulders, over the saccos, a bishop wears the omophorion. This is a long, wide fabric usually adorned with crosses. It is wrapped around the shoulders of the bishop so that one end falls in front and the other behind. Omophorion is a Greek word meaning "that which goes over the shoulders" and is exclusively an episcopal vestment. As with the priest and his epitrachelion, the bishop may not conduct any service without his omophorion. It reminds the bishop that he must be concerned for the salvation of the fallen like the good shepherd who, when he has found the lost sheep, carries it home on his shoulder.
At all times, as part of his normal attire and for services, the bishop wears a panagia around his neck in addition to a cross. The panagia, which means "all-holy" in Greek, is a small, round icon of the Saviour or the Theotokos, sometimes adorned with precious stones.
When serving, the bishop wears a miter on his head, adorned with small icons and precious stones. According to some, it signifies the crown of thorns which was placed on the head of the Saviour, and to others it represents the Gospel of Christ to which the bishop always remains subject. Archimandrites wear the miter as well, and in exceptional cases a ruling bishop can grant the right to wear one to the more worthy archpriests in place of the kamilavka. During the divine services the bishops use a staff as a sign of ultimate pastoral authority. A staff is also granted to archimandrites and abbots as heads of monasteries.
During the service an "orlets," a circular rug with the image of an eagle flying over a city, is put under the bishop’s feet. This symbolizes that the bishop should soar from the earthly to the heavenly like an eagle, and as an eagle can see clearly over distances, so must a bishop oversee all parts of his diocese.
Priests comprise the second rank of the sacred ministry under the bishop. Priests may serve, with an episcopal blessing, all the Mysteries and ecclesiastical services, with the exception of the Mystery of Ordination and the sanctification of Holy Chrism or an Antimensis. The congregation of Christians subject to the supervision of the priest is termed his parish. The more worthy and distinguished priests are granted the title of archpriest; the first among these priests is called a protopresbyter. If a priest is also a tonsured monk he is known as a hieromonk. Hieromonks appointed to direct monasteries, or those honored independently of any appointment, are usually given the title of igumen or abbot. Those of a higher rank are called archimandrites, and bishops are chosen from this rank.
The vestments of a priest include the under-vestment or sticharion, the epitrachelion (stole), the belt, the cuffs, and the phelonion. The under-vestment is just a simpler form of sticharion, differing from the sticharion in that the sleeves are narrow with laces at the wrist, and it is usually made of a fine, white material. The white color reminds the priest that he must always be of pure soul and lead a blameless life. It also recalls the tunic which the Lord Jesus Christ wore on earth and in which He accomplished our salvation.
The stole or epitrachelion is similar to the deacon’s orarion, only it is worn around the neck and comes down in front so that the two inner edges are fastened together for convenience. It signifies the double portion of grace bestowed on a priest, in comparison to that of a deacon, for the celebration of the Mysteries. The priest may not conduct any service without his epitrachelion, just as a deacon must have his orarion. The belt is worn over the epitrachelion and under-vestment and signifies readiness to serve the Lord. It also symbolizes the divine power that strengthens the priest during the course of his serving. The belt also recalls the towel which the Saviour was given for the washing of the disciples’ feet at the Mystical Supper.
The phelonion is worn over the other garments. It is a long and wide cape without sleeves with an opening for the head at the top and cut away in front to give the hands freedom of movement. In its form it resembles the purple mantle which the Lord was given during His passion. The ribbons sewn on it recall the streams of blood which flowed over His garments. In addition to this the phelonion reminds the priests of the garment of righteousness with which they must be vested as servants of Christ. A priest wears a pectoral cross around his neck, over the phelonion. For long and dedicated service a priest is given an award called a nabedrennik or thigh shield, which is a stiffened, rectangular cloth hung on the right hip from the shoulder by a strap fastened at two upper corners, and which signifies a spiritual sword. Other awards are the skoufia and kamilavka (head coverings), and another diamond-shaped cloth, similar to the nabedrennik, worn on the right hip, called a palitsa (in which case the former is worn on the left). It also represents the spiritual sword, the Word of God with which the celebrant must battle disbelief and irreverence.
Deacons form the third and lowest rank of the sacred ministry; in Greek "deacon" means a "server." Deacons assist a bishop or priest during the serving of the Divine Liturgy or other Mysteries and services, but they may not serve alone. The participation of a deacon in the divine services is not obligatory, and therefore many churches conduct services without them. Some deacons, particularly in cathedral churches, are deemed worthy of the title of protodeacon. Monks who have received the rank of deacon are called hierodeacons, and the senior of them is called an archdeacon.
The vestments of the diaconate are the sticharion, the orarion and the cuffs.The sticharion is a long garment, open down the length of the sides for a deacon, but entirely unslitted for servers, in the form of a cross with an opening for one’s head and with wide sleeves. The deacon’s sticharion may also be worn by subdeacons. The right to wear a sticharion may also be granted to readers and servers. The sticharion signifies purity of soul, necessary for a person of ecclesiastical rank.
The orarion is a long, wide band of the same material as the sticharion with fringe on the ends. It is worn over the left shoulder on top of the sticharion. For simple deacons it is worn as shown, for proto-deacons it is wound once around the body. The orarion signifies the Grace of God which the deacon received in the Mystery of Ordination. The cuffs or manacles are of the same material as the sticharion, and are worn around the wrists and laced with cords. They remind those conducting the services that they celebrate the Mysteries or partake of the Mysteries of the Christian faith not by their own powers, but by the power and Grace of God. They also remind us of the bonds that tied the hands of the Savior during His passion.