The promotion of peace in the world is an integral part of the Church's mission of continuing Christ's work of redemption on earth. In fact, the Church is, in Christ, a “ ‘sacrament' or sign and instrument of peace in the world and for the world”.1089John Paul II, Message for the 2000 World Day of Peace, 20: AAS 92 (2000), 369. The promotion of true peace is an expression of Christian faith in the love that God has for every human being. From a liberating faith in God's love there arises a new vision of the world and a new way of approaching others, whether the other is an individual or an entire people. It is a faith that transforms and renews life, inspired by the peace that Christ left to his disciples (cf. Jn 14:27). Moved solely by this faith, the Church intends to promote the unity of Christians and a fruitful cooperation with believers of other religions. Differences of religion must not be a cause of conflict; the shared quest for peace on the part of all believers is a vital source of unity among peoples.1090Cf. John Paul II, Message for the 1988 World Day of Peace, 3: AAS 80 (1988), 282-284. The Church calls on individuals, peoples, States and nations to share her concern for re-establishing and consolidating peace, placing particular emphasis on the important role of international law1091Cf. John Paul II, Message for the 2004 World Day of Peace, 9: AAS 96 (2004), 120..
The Church teaches that true peace is made possible only through forgiveness and reconciliation.1092Cf. John Paul II, Message for the 2002 World Day of Peace, 9: AAS 94 (2002), 136-137; John Paul II, Message for the 2004 World Day of Peace, 10: AAS 96 (2004), 121. It is not easy to forgive when faced with the consequences of war and conflict because violence, especially when it leads “to the very depths of inhumanity and suffering”,1093John Paul II, Letter on the occasion of the fiftieth anniversary of the outbreak of the Second World War (27 August 1989), 2: L'Osservatore Romano, English edition, 4 September 1989, p. 1. leaves behind a heavy burden of pain. This pain can only be eased by a deep, faithful and courageous reflection on the part of all parties, a reflection capable of facing present difficulties with an attitude that has been purified by repentance. The weight of the past, which cannot be forgotten, can be accepted only when mutual forgiveness is offered and received; this is a long and difficult process, but one that is not impossible1094Cf. John Paul II, Message for the 1997 World Day of Peace, 3 and 4: AAS 89 (1997), 193..
Mutual forgiveness must not eliminate the need for justice and still less does it block the path that leads to truth. On the contrary, justice and truth represent the concrete requisites for reconciliation. Initiatives aimed at establishing international judicial bodies are therefore appropriate. In virtue of the principle of universal jurisdiction and guided by suitable procedural norms that respect the rights of the accused and of the victims, such bodies are able to ascertain the truth about crimes perpetrated during armed conflicts.1095Cf. Pius XII, Address to the Sixth International Congress on Criminal Law (3 October 1953): AAS 65 (1953), 730-744; John Paul II, Address to the Diplomatic Corps (13 January 1997), 4: L'Osservatore Romano, English edition, 15 January 1997, p. 7; John Paul II, Message for the 1999 World Day of Peace, 7: AAS 91 (1999), 382. However, in order to re-establish relationships of mutual acceptance between divided peoples in the name of reconciliation, it is necessary to go beyond the determination of criminal behaviour, both of commission and omission, and the procedures for seeking reparation.1096Cf. John Paul II, Message for the 1997 World Day of Peace, 3, 4, 6: AAS 89 (1997), 193, 196-197. It is necessary, moreover, to promote respect for the right to peace. This right “encourages the building of a society in which structures of power give way to structures of cooperation, with a view to the common good”1097John Paul II, Message for the 1999 World Day of Peace, 11: AAS 91 (1999), 385..
It is through prayer that the Church engages in the battle for peace. Prayer opens the heart not only to a deep relationship with God but also to an encounter with others marked by respect, understanding, esteem and love.1098Cf. John Paul II, Message for the 1992 World Day of Peace, 4: AAS 84 (1992), 323-324. Prayer instils courage and lends support to all “true friends of peace”,1099Paul VI, Message for the 1968 World Day of Peace: AAS 59 (1967), 1098. those who love peace and strive to promote it in the various circumstances in which they live. Liturgical prayer is “the summit towards which the action of the Church tends and, at the same time, the source from which she draws her strength”.1100Second Vatican Ecumenical Council, Constitution Sacrosanctum Concilium, 10: AAS 56 (1964), 102. In particular, the Eucharistic celebration, “the source and summit of the Christian life”1101Second Vatican Ecumenical Council, Constitution Lumen Gentium, 11: AAS 57 (1965), 15., is a limitless wellspring for all authentic Christian commitment to peace1102The eucharistic celebration begins with a greeting of peace, the greeting of Christ to his disciples. The Gloria is a prayer for peace for all the people of God on the earth. Prayer for peace is made through the anaphora at Mass: an appeal for the peace and unity of the Church, for the peace of the entire family of God in this life, for the advancement of peace and salvation in the world. During the communion rite the Church prays that the Lord will “grant us peace in our day” and remembers Christ's gift that consists of his peace, invoking “the peace and unity of his Kingdom”. Before communion, the entire assembly exchanges a sign of peace and the assembly prays that the Lamb of God, who takes away the sins of the world will “grant us peace”. The eucharistic celebration concludes with the assembly being dismissed in the peace of Christ. There are many prayers that invoke peace for the world. In these, peace is sometimes associated with justice, for example, as in the opening prayer for the Eighth Sunday in Ordinary Time, in which the Church asks God to guide the course of world events in justice and peace, according to his will..
The World Days of Peace are particularly intense moments of prayer for peace and for the commitment to build a world of peace. Pope Paul VI instituted these Days to dedicate to “thoughts and resolutions of Peace a special observance on the first day of the civil year”.1103Paul VI, Message for the 1968 World Day of Peace: AAS 59 (1967), 1100. The Papal Messages on these annual occasions represent a rich source for the renewal and development of the Church's social doctrine and show the Church's constant pastoral activity aimed at the promotion of peace. “Peace expresses itself only in peace, a peace which is not separate from the demands of justice, but which is fostered by personal sacrifice, clemency, mercy and love”1104Paul VI, Message for the 1976 World Day of Peace: AAS 67 (1975), 671.. “As far as the Church is concerned, the social message of the Gospel must not be considered a theory, but above all else a basis and a motivation for action”. (Centesimus Annus, 57) I. PASTORAL ACTION IN THE SOCIAL FIELD