34 From this it follows, as an immediate consequence, that the peace of Christ can only be a peace of justice according to the words of the prophet "the work of justice shall be peace" ( Isaias xxxii, 17) for he is God "who judgest justice." ( Psalms ix, 5) But peace does not consist merely in a hard inflexible justice. It must be made acceptable and easy by being compounded almost equally of charity and a sincere desire for reconciliation. Such peace was acquired for us and the whole world by Jesus Christ, a peace which the Apostle in a most expressive manner incarnates in the very person of Christ Himself when he addresses Him, "He is our peace," for it was He Who satisfied completely divine justice by his death on the cross, destroying thus in His own flesh all enmities toward others and making peace and reconciliation with God possible for mankind. ( Ephesians ii, 14) Therefore, the Apostle beholds in the work of Redemption, which is a work of justice at one and the same time, a divine work of reconciliation and of love. "God indeed was in Christ, reconciling the world to himself." (II Corinthians v, 19) "God so loved the world, as to give his only begotten Son." ( John iii, 16)
Source: Ubi Arcano Dei Consilio (Vatican.va)