The sacrament of Orders comprises the threefold ministry of Bishop, Priest, and Deacon. Ordination is the sacrament by which a person enters into one of these three ministerial Orders.

"Through sacred Ordination certain of the Christian faithful are appointed in the name of Christ and receive the gift of the Holy Spirit to shepherd the Church with the word and grace of God"
- Rite of Ordination, General Introduction, 1.