73 The priest must not think that ordination makes everything easy for him and screens him once and for all from every temptation or danger. Chastity is not acquired all at once but results from a laborious conquest and daily affirmation. Our world today stresses the positive values of love between the sexes but has also multiplied the difficulties and risks in this sphere. In order to safeguard his chastity with all care and affirm its sublime meaning, the priest must consider clearly and calmly his position as a man exposed to spiritual warfare against seductions of the flesh in himself and in the world, continually renewing his resolution to give an ever increasing and ever better perfection to the irrevocable offering of himself which obliges him to a fidelity that is complete, loyal and real.
Source: Sacerdotalis Caelibatus (Vatican.va)