This Holy Sacrament was established on the Day of the Pentecost when the Disciples received the Holy Spirit. Jesus chose the apostles to continue the work of the Church, to preach the Word, administer sacraments, and govern the church.
As the Acts of the Apostles inform us by laying their hands, they ordained priests and later, priests and bishops and gave them the power of the Holy Spirit that they received on the Pentecost Day. This is called ordination. When the Holy Church was growing, more elected servants of God were needed, and more ordinations took place. More Churches, dioceses and later Archdioceses and Patriarchates were established.
Our priests, deacons and bishops today continue the work of these original apostles of Jesus and are successors of them. Jesus ordained the first apostles, who in turn ordained other priests and bishops, who in turn also ordained others to succeed them, and so on and so forth down to the present. Thus, each generation of clergy is traced directly back to the Apostles and Christ. This is called Apostolic Succession, a chain that never broke from the day of the Pentecost. This is important since it maintains continuity of the Church in origin and in doctrine with the early teachings. It's continuity of descent proves that the Church is one, holy, catholic and apostolic.
The Priest has the great responsibility for themselves to keep themselves holy according to the teachings of the Gospel. They have to serve the ministry with dignity and teach the Gospel to the faithful, and explain all the Holy traditions that derive from the holy Bible. Because of these reasons the lay people respect their clergy, who dedicated their life to the mission of Christ and to the salvation of the souls of their faithful.
The faithful kiss the hand of the clergy because they are filled with the power of the Holy Spirit from the day of their ordination, and it shows respect to the Holy Spirit since Holy Communion is administered with this hand of the clergy. They do not shake his hand. Those who do not venerate the hand of an orthodox clergy, express that they do not believe that they carry the power of the Holy Spirit through their ordination. The shaking of hands belongs to the secular world, not in the ecclesiastical world.
Clergy are addressed as "Father" since they are whom we received spiritual birth in Christ through baptism. Bishops are addressed as "Your Grace." They oversee the sacramental and educational life of Christians within their diocese, a defined geographical area.
Women are not ordained in the Orthodox Church. This follows sacred tradition and example established by Jesus and His apostles.
