The Sacrament of Holy Orders creates a priest.

"[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 — the orders of bishop, priest, and deacon" (Catechism of the Catholic Church, 1536).

In the Sacrament of Holy Orders, or Ordination, the priest being ordained vows to lead other Catholics by bringing them the sacraments (especially the Eucharist), by proclaiming the Gospel, and by providing other means to holiness.

Holy Orders differs from the other sacraments because it can only be administered by a bishop. Only a bishop has the power to ordain priests. An ordinary priest cannot pass on his power to another.

The Sacrament of Holy Orders is not received all at once. It is is given by degrees, in successive stages. At each stage, there is an increase in sanctifying grace and powers:

• A deacon gains the power to baptize, to preach, and to administer the Eucharist.
• A priest gains the power to change bread and wine into the Body and Blood of Christ and to forgive sins.
• A bishop gains the power to Confirm and to ordain.