Pope Paul VI
Sacerdotalis Caelibatus §37
Sacerdotalis Caelibatus: On the Celibacy of the Priest
37 The most recent sovereign pontiffs who preceded Us, making use of their doctrinal knowledge and spurred on by ardent zeal, strove to enlighten the clergy on this matter and to urge them to its observance. (75) We do not wish to fail to pay homage to them, especially to Our well-loved immediate predecessor, whose memory is still fresh in the hearts of men all over the world. During the Roman Synod, with the sincere approval of all the clergy of the city, he spoke as follows: "It deeply hurts Us that . . . anyone can dream that the Church will deliberately or even suitably renounce what from time immemorial has been, and still remains, one of the purest and noblest glories of her priesthood. The law of ecclesiastical celibacy and the efforts necessary to preserve it always recall to mind the struggles of the heroic times when the Church of Christ had to fight for and succeeded in obtaining her threefold glory, always an emblem of victory, that is, the Church of Christ, free, chaste and catholic." (76)
Source: Sacerdotalis Caelibatus (Vatican.va)