The ordained ministry or ministerial priesthood is at the service of the baptismal priesthood. The saving mission entrusted by the Father to his incarnate Son was committed to the apostles and through them to their successors: they receive the Spirit of Jesus to act in His name and in His person. The ordained minister is the sacramental bond that ties the liturgical action to what the apostles said and did and, through them, to the words and actions of Christ, the source and foundation of the sacraments. (CCC 1120)

“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…It includes three degrees of order: episcopate, presbyterate, and diaconate” (CCC 1536).