“Holy Orders is the sacrament through which the mission entrusted by Christ to his apostles continues to be exercised in the Church until the end of time: thus it is the sacrament of apostolic ministry. It includes three degrees: episcopate (Bishop,) presbyterate (Priest,) and diaconate (deacon.)” (CCC 1536)

There are two ways in which the sacrament of Holy Orders differs from the other sacraments.

Holy Orders can be administered only by a bishop. Only a bishop has the power to ordain priests.

Holy Orders is not received all at once.

Holy Orders is given by degrees, by successive steps.

Three successive stages:

Deaconship, priesthood, and bishopric are the three stages in the sacrament of Holy Orders. At each stage, as in every sacrament, there is a celebration of grace and an imprinting of a character upon the soul which calls one to deeper communion with Christ and His Church.
Each stage has certain ministries associated with it.

For the deacon it is the right to baptize, to preach, and to administer Holy Communion.
For the priest it is to preside at the Eucharistic table and to forgive sins.
For the bishop, who alone has the complete fullness of the priesthood, it is the ministry to confirm and to ordain—to pass the priesthood on to others in the sacrament of Holy Orders.