Catholic peace traditions begin with its biblical and classical origins and continue on to the current practice in the twenty-first century. Because of its long history and breadth of geographical and cultural diversity, this Catholic tradition encompasses many strains and influences of both religious and secular peacemaking and many aspects of Christian pacifism, just war and nonviolence.

Catholic tradition as a whole supports and favours peacemaking efforts.Kemmetmueller, Donna Jean. "Peace: The Challenge of Living the Catholic Tradition", Peace and Conflict Monitor. May 9, 2005 Peacemaking is an integral part of Catholic social teaching."Glossary", CatholicSocialTeaching.org.uk

Definitions

The history of peacemaking in the Catholic tradition reflects the religious meanings of peace, tied to positive virtues, such as love, and to the personal and social works of justice. The Greek word for peace is eirene; Roman pax, and in the Hebrew Bible, shalom.

For the earliest Romans, "pax" meant to live in a state of agreement, where discord and war were absent. In his Meditations, or To Himself, the Roman Emperor Marcus Aurelius expresses peace as a state of unperturbed tranquility. The English word "peace" derives ultimately from its root, the Latin "pax".

Shalom () is the word for peace in the Hebrew Bible (Tanakh or ), and has other meanings also pertaining to well being, including use as a greeting.

Eirene The Greek meaning for peace, contained in the word eirene, evolved over the course of Greco-Roman civilization from such agricultural meanings as prosperity, fertility, and security of home contained in Hesiod's Works and Days, to more internal meanings of peace formulated by the Stoics, such as Epictetus.

Eirene is the word that the New Testament generally uses for peace, one of the twenty words used by the Septuagint, the Greek version of the Hebrew Bible used in the largely Greek-speaking Jewish communities throughout the Greco-Roman world. It is chiefly through the Septuagint's use of Greek that the Greek word eirene became infused with all the religious imagery and richness of the word shalom in the Hebrew Bible that had evolved over the history of the Jewish people. Subsequently, the use of the Greek Bible as the basis for St. Jerome's Vulgate translation into Latin then brought all the new meanings of eirene to the Latin word pax and transformed it from a term for an imposed order of the sword, the Pax Romana, into the chief image of peace for Western Christianity.Musto, Ronald G., The Catholic Peace Tradition, Orbis Books, 1986

New Testament

The Gospels present the birth of Jesus as ushering in a new age of peace. In Luke, Zechariah celebrates his son John: And you, child, will be called prophet of the Most High, for you will go before the Lord to prepare his ways, to give his people knowledge of salvation through the forgiveness of their sins, because of the tender mercy of our God by which the daybreak from on high will visit us to shine on those who sit in darkness and death's shadow, to guide our feet into the path of peace."Luke 1: 76-79", The New American Bible, United States Conference of Catholic Bishops, 2002

And later, the angels appear to the shepherds at Bethlehem, "And suddenly there was a multitude of the heavenly host with the angel, praising God and saying: 'Glory to God in the highest and on earth peace to those on whom his favor rests'" – a peace distinct from the Pax Romana.

The Sermon on the Mount (Mt. 5:1-16) and the Sermon on the Plain (Lk. 6:20-45) combine with the call to "love your enemies" (Mt. 5:38-48) to encapsulate Jesus' teachings on peacemaking. According to Gabriel Moran, the Sermon on the Mount does not advocate submission to oppressors, but rather a strategy to "de-hostilize enemies in order to win them over".Moran, Gabriel. "Roman Catholic Tradition and Passive Resistance", New York University

The account of the healing of the centurion's servant suggests to John Eppstein that Jesus did not view military service as sinful, since rather than reprove the soldier for his profession, Jesus praised him for his faith. Nor did Peter require Cornelius to resign his commission or desert upon being baptized.Eppstein, John. The Catholic Tradition of the Law of Nations, Burns & Oates, London, 1935 John the Baptist's advice to soldiers was, "Do not practice extortion, do not falsely accuse anyone, and be satisfied with your wages."

Early Church Early Christianity was relatively pacifist.McCormick, Patrick. "Catholic Social Teaching & the Catholic Intellectual Tradition", The Catholic University Clement of Alexandria wrote, "If you enroll as one of God's people, heaven is your country and God your lawgiver. And what are his laws? You shall not kill, You shall love your neighbor as yourself. To him that strikes you on the one cheek, turn to him the other also." (Protrepticus 10) "Selected Quotations", War, Peace and Conscience in the Catholic Tradition

The early Christians anticipated the eminent return of the Lord in glory, even to the extent that Paul had to tell some of them to get back to work. Generally they were not deeply involved in the larger community. As it became apparent that a more nuanced understanding was called for, Christians came to realize that if they were to survive socially they could not remain within the confines of their own community.Massaro, S.J. and Shannon, Thomas A., Catholic Perspectives on Peace and War, Sheed & Ward, 2003

Christians in the Roman Army

St. Paul wrote, "Let every person be subordinate to the higher authorities, for there is no authority except from God, and those that exist have been established by God. ... This is why you also pay taxes, for the authorities are ministers of God, devoting themselves to this very thing. Pay to all their dues, taxes to whom taxes are due, toll to whom toll is due, respect to whom respect is due, honor to whom honor is due."

The early Christian church believed that Christians should not take up arms in any war, and so struggled attempting to balance the obligation to be a good citizen and the question of whether it was permissible to take up arms to defend one's country. There developed a gap between the reasoning of the moral theorists and the practice of the private citizen.

As early as second century, Christians began to participate in Roman military, police, and government in large numbers. Military service was one way available to make a living, and on the borders of the empire there was a need to defend against barbarian incursions. As the army came to take on duties more in the line of police work: traffic and customs control, firefighting, the apprehension of criminals and bandits, maintaining the peace, quelling street brawls, and performing the roles of engineering, clearance, and other works of building for which the Roman army was well known, this choice became less problematic. The numbers of soldiers that came to be counted among the later martyrs indicates that many Christians served in the military, despite their abhorrence of war.

From about the middle of the second century, officers in the Roman army were expected to participate in the Imperial Cult and sacrifice to the emperor. During the reign of Diocletian this obligation was extended to the lower ranks, as a test for those suspected of being Christian. Christians were therefore counseled not to enlist so as to avoid needless blood guilt and the risk of idolatry, but should nonetheless continue to pray for the civil authorities.

Among the better-known soldier saints are Saint Marinus, Marcellus of Tangier, and Maximilian of Tebessa, and Martin of Tours.

Martyrdom as non-violent protest

Persecutions were sporadic and in the third century, largely local. By and large the Roman government didn't pay much attention to Christianity.

Christians sought to live the injunction to love their enemies while resisting their evil, even if this involved persecution and death: these were the martyrs. The word martyr is the Greek for "witness". The early martyrs followed a long-standing tradition; John the Baptist was beheaded for "speaking truth to power". They also had as examples St. Stephen, the apostles James, Philip, and Matthew, and others.Philpott, Daniel. "The Early Church", Notre Dame University According to Josephine Laffin, martyrdom demonstrated to all that Christ had overcome death, and that the Holy Spirit sustained the Church in its fight against darkness and evil.Laffin, Josephine. What Does it Mean to be a Saint?: Reflections on Mary MacKillop, Saints and Holiness in the Catholic Tradition, p. 85, Wakefield Press, 2010

Martyrs of Cordoba

The Martyrs of Córdoba were forty-eight Christian martyrs living in the ninth-century Muslim-ruled Al-Andalus. Their hagiography describes in detail their executions for deliberately sought capital violations of Muslim law in Al-Andalus. The martyrdoms recorded by Eulogius took place between 851 and 859; with few exceptions, the Christians invited execution by making public statements tactically chosen to invite martyrdom by appearing before the Muslim authorities to denounce Islam. The martyrs caused tension not only between Muslims and Christians, but within the Christian community. In December 852 Church leaders called a council in Cordoba, which honored those fallen but called on Christians to refrain from seeking martyrdom.

Recent historical interpretation of the martyr movement reflect questions on its nature. Kenneth Baxter Wolf sees its cause in "spiritual anxiety" and the penitential aspect of ninth-century Iberian Christianity.Wolf, Kenneth Baxter. Christian Martyrs in Muslim Spain, New York: Cambridge University Press, 1987 Clayton J. Drees"Sainthood and Suicide. The Motives of the Martyrs of Córdoba, A.D. 850-859", Journal of Medieval and Renaissance Studies 20, 1, 1990: 59-89 sees their motives in a "pathological death-wish, the product of unexpressed hatred toward society that had turned inward against themselves" and other innate "psychological imbalances". Jessica A. Coope suggests that it reflects a protest against the process of assimilation, and that the martyrs demonstrated a determination to assert Christian identity.Coope, Jessica A., The Martyrs of Córdoba: Community and Family Conflict in an Age of Mass Conversion, p. 14, University of Nebraska Press, 1995

Age of Constantine

With the triumph of Constantine as sole Roman emperor in 313, the church of the martyrs now found itself an accepted and favored religion, soon to become the official religion of the state. Constantine had an emblem inscribed on the shields of his soldiers that has been various described as representing the "Unconquerable Sun" or as a Chi-Rho. Eileen Egan quotes Burkhardt's observation that this was "an emblem which every man could interpret as he pleased, but which the Christians would refer to themselves."

As the religion of the empire, its survival was tied to the fate of the Empire. The threat of increased barbarian incursions therefore threatened both, and defense of the Empire was appropriate in order to protect Christianity. The early trend toward pacifism became muted.

Ambrose of Milan, former Pretorian Prefect of northern Italy before being elected bishop of Milan, preserved the Christian presumption against the use of violence, unless it was needed to protect important social values. While rejecting resorting to violence in self-defense, he argued that charity demanded one protect one's neighbour.Duncan C.Ss.R., Bruce. "The Struggle to Develop a Just War Tradition in the West", Australian Catholic Social Justice Council, April 8, 2003 "He who does not ward off injury from his comrade, when he is able to, is just as guilty as he who does the injury."Egan, Eileen. Peace Be with You: Justified Warfare or the Way of Nonviolence, Wipf and Stock Publishers, 2004