Speaking about the clergy, what are the clerical offices in the Orthodox Church and what is their significance?
The Orthodox Church has the three classical Christian offices: bishop, priest (or presbyter) and deacon.
The bishop is the highest office since the bishop is the one responsible to guide the life of the church, to guard the faith and to preserve the unity of the churchly body in truth and love. Bishops are traditionally taken from the monks, and by a regulation dating from the 6th century, must be unmarried. A widowed priest or any unmarried man can be elected to the office of bishop.
The priests (or presbyters) carry on the normal pastoral functions in the Church and lead the local parish communities. They are usually married men. They must be married prior to their ordination and are not allowed to marry once in the priestly state. Single priests or widowers may marry but in this case, they are no longer allowed to function in the ministry.
At the present time, the diaconate in the Church is usually a step to the priesthood, or else it exists solely as a liturgical ministry. The deacon may also be a married man, with the same conditions as those for the married priesthood.