Catechism of the Catholic Church
1575 Christ himself chose the apostles and gave them a share in his mission and authority. Raised to the Father's right hand, he has not forsaken his flock but he keeps it under his constant protection through the apostles, and guides it still through these same pastors who continue his work today. 61 Thus, it is Christ whose gift it is that some be apostles, others pastors. He continues to act through the bishops. 62
1576 Since the sacrament of Holy Orders is the sacrament of the apostolic ministry, it is for the bishops as the successors of the apostles to hand on the "gift of the Spirit," 63 the "apostolic line." 64 Validly ordained bishops, i.e., those who are in the line of apostolic succession, validly confer the three degrees of the sacrament of Holy Orders. 65
English Translation of the Cathechism of the Catholic Church for the United States of America © 1997, United States Catholic Conference, Inc.