78 The priestly life certainly requires an authentic spiritual intensity in order to live by the Spirit; (127) it requires a truly virile asceticism—both interior and exterior—in one who, belonging in a special way to Christ, has in Him and through Him "crucified the flesh with its passions and desires," (128) not hesitating to face arduous and lengthy trials in order to do so. (l29) In this way Christ's minister will be the better able to show to the world the fruits of the Spirit, which are "charity, joy, peace, patience, benignity, goodness, longanimity, mildness, faith, modesty, continency, chastity.'' (l30)
Source: Sacerdotalis Caelibatus (Vatican.va)