13 Therefore, Venerable Brethren, We pray you and exhort you in the mercy and charity of Jesus Christ, strive with all zeal and diligence not only to urge the faithful entrusted to your care to abandon hatred and to pardon offences; but, and what is more immediately practical, to promote all those works of Christian benevolence which bring aid to the needy, comfort to the afflicted and protection to the weak, and to give opportune and appropriate assistance of every kind to all who have suffered from the war. It is Our especial wish that you should exhort your priests, as the ministers of peace, to be assiduous in urging this love of one's neighbour and even of enemies which is the essence of the Christian life, and by "being all things to all men'' and giving an example to others, wage war everywhere on enmity and hatred, thus doing a thing most agreeable to the loving Heart of Jesus and to him who, however unworthy, holds His place on earth. In this connection Catholic writers and journalists should be invited to clothe themselves "as elect of God, holy and beloved, with pity and kindness.'' Let them show this charity in their writings by abstaining not only from false and groundless accusations but also from all intemperance and bitterness of language, all of which is contrary to the law of Christ and does but reopen sores as yet unhealed, seeing that the slightest touch is a serious irritant to a heart whose wounds are recent.
Source: Pacem, Dei Munus Pulcherrimum (Vatican.va)