"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" (Catechism of the Catholic Church, paragraph 1536). At ordination, the one called by God promises to embrace the disciplines of the Church more fully: promising obedience, forsaking his personal wants for the good order of the Church; promising celibacy, forsaking his own ego in favor of the Kingdom; and promising stability, remaining faithful to the People of God in his diocese of incardination throughout his life. As long as he remains faithful to these promises, remaining faithfully in communion with the Church, he receives the permission, also known as faculties, to lead the community entrusted to him in the sacred rites of the Church, in the study of the Deposit of Faith, and in the administration of the goods of the Church through careful steardship.
"Though they differ from one another in essence and not only in degree, the common priesthood of the faithful and the ministerial or hierarchical priesthood are nonetheless interrelated: each of them in its own special way is a participation in the one priesthood of Christ." vatican.va
For more information, please go to The Office of Vocations at the Archdiocese of Portland.