The whole Church is a priestly people. Through Baptism, all the faithful share in the priesthood of Christ. This participation is called the "common priesthood of the faithful." Based on this common priesthood and ordered to its service, there exists another participation in the mission of Christ: the ministry conferred by the sacrament of Holy Orders, where the task is to serve in the name and in the person of Christ the Head in the midst of the community. (CCC 1591)
The Church confers the sacrament to Holy Orders on baptized men, whose suitability for the exercise of the ministry has been duly recognized. Church authority alone has the responsibility and right to call someone to receive the sacrament of Holy Orders. (CCC 1598)