Did Christianity had a well-defined concept of a holy war?

Unlike Islam, Christianity had no well-defined concept of holy war before the Middle Ages. Christ had no armies at his disposal, nor did his early followers. Only in AD 312, after the conversion to Christianity of the Roman emperor Constantine I (306–337), did the religion come into direct contact with statecraft and warfare. Within a century, Christianity and the Roman Empire were fused tightly together. Christians in government found themselves faced with questions of life and death, war and peace—questions that their religion had not wrestled with before. In the fifth century, St. Augustine outlined the necessary conditions for a Christian leader to wage a just war, but he was quick to insist that the faithful not engage in wars of religious conversion or for the purpose of destroying heresies or killing pagans. Warfare was a necessary evil sometimes forced upon a good leader—it was not to be a tool of the church. The collapse of Roman power in the western Mediterranean did not spell a similar loss of power for Christianity because the Germanic barbarians who carved up the Western empire were themselves Christians. The Christian faith, therefore, remained the faith of the large majority of people throughout Europe, the Near East, and North Africa.

Mohammed founded a new religion. Christianity’s first serious competitor.

Christianity’s first serious competitor did not arise until the seventh century, when the prosperous Arab merchant Mohammed founded a new religion. Islam, or “submission to the will of God,” was and is a scrupulously monotheistic faith. Muslims believe that the God of the Jews and Christians made his word known to Mohammed, who then “recited” what he had been told. All these prophecies were carefully preserved and later written down in the Koran. Mohammed noted that God had frequently spoken to his people through the prophets of the Old Testament, but time and again the Jews had ignored these holy men. Mohammed accepted Jesus as a blessed prophet who was fundamentally misunderstood by both Jews and Christians: the former persecuted him, and the latter proclaimed him God. Mohammed and his followers believed that God now bestowed his infallible word on a new people. Those who embraced the humble life of submission, good works, and prayer that the Koran enjoined would enjoy the riches of heaven for eternity after death.

Mohammed beginning his prophecies and preaching. The concept of Jihad

Mohammed began his prophecies and preaching in Mecca, a trading city in Arabia. In 622, he moved to nearby Medina and became that city’s ruler. There, Mohammed inspired more than just a religion. Because the Prophet was both a political and religious leader, Islam was at once a faith and a means of government. Commerce, justice, diplomacy, and war were built into the bedrock of the religion. Unlike Christian leaders, who tried to reconcile their prestige, power, and wealth with Christ’s life of poverty, Muslims had in their founder a model of a worldly and a spiritual leader. Mohammed waged war, first against other Arab towns and then against Mecca itself. Muslims called each of these wars a jihad, or “struggle.” Soldiers who died in a jihad were thought to be martyrs of the faith. At the moment of their deaths, Muslims believed, the fallen in a jihad rose instantly from the sands of battle to their reward in a lush and sensual paradise. Yet not every war was a jihad. It could only be waged against unbelievers, those who refused to accept the one God, and those who sought to harm Islam. Jews and Christians, from the Muslim point of view, worshiped the true God, failing only to accept the prophecy of Mohammed. For that reason, they were misguided, but they were not pagans. They were the “People of the Book,” who should remain free to retain their religious practices in the lands conquered by Islam. If they actively persecuted or hindered the advance of Islam, however, they too were legitimate targets of jihad.

The vision of expansionism

After the conquest of Arabia, Mohammed envisioned the continued expansion of Islam. Indeed, expansionism working hand in hand with jihad became an important component in the Muslim worldview. Traditional Islamic thought divided the world into two spheres, the Dar al-Islam (Abode of Islam) and the Dar al-Harb (Abode of War). The Dar al-Islam consisted of those lands directly ruled by Muslims and subject to Islamic law. The Dar al-Harb, which included the Christian world, was the place in which Muslims were enjoined to wage jihad against unbelievers, capturing their lands and subjecting their peoples. In this way it was believed that the Dar al-Harb would shrink and the Dar al-Islam would correspondingly increase until it covered the entire world. The rapid expansion of Islam was truly remarkable. After Mohammed’s death in 632 a series of caliphs (successors) waged energetic jihads against neighboring peoples. Within a century, Arab Muslims had conquered Persia, Egypt, and Syria. Such rapid expansion led to rifts within the faith itself. The most important and long-lasting of these, the division between Sunni and Shia, occurred in the late seventh century. The original split was the result of a succession dispute, but the two groups soon began to drift apart theologically as well. The minority Shi’ites looked to their imams, who led them and attained for them the esoteric truths of the Koran. The majority Sunnites insisted on the political and religious unity of the Islamic state and rejected the leadership of the imams.

The defining of the concept of a Holy war in Christianity

It would be too strong to say that it was the idea of jihad that led to Christianity’s own concept of holy war. The Christians of the eastern Roman Empire, known to historians as the Byzantine Empire, were willing enough to flirt with the idea of holy war during Emperor Heraclius’s (610–641) campaigns against the Persians. When the forces of Islam exploded onto Byzantine lands shortly thereafter, however, the idea did not resurface. Christians were too fragmented into opposing sects to organize around such a fundamentally central doctrine. For minority Christian sects in Syria and Egypt, the arrival of Muslims was actually good news. The new Arab leaders allowed them a freedom of worship that the emperor in Constantinople did not. Despite their close proximity to Islamic kingdoms, Byzantine Christians, it appears, never developed a religious rationale for waging or condoning holy war. It was in western Europe that the concept of Christian holy war took root and grew. Muslim conquerors who swept through all of Christian North Africa also crossed the Strait of Gibraltar and established their rule over Spain. By the eighth century, Muslim expeditionary forces were crossing the Pyrenees and marching into the heart of Catholic Europe. In 732, at the famous Battle of Tours, Frankish leader Charles Martel defeated the Muslims, driving them back into Spain. Spain was still Christendom, however, and Europeans believed strongly that Muslims should not be there. From their perspective, these lands were consecrated to Christ. It was not right that infidels should dwell there, let alone rule. Was it not self-evident that a Christian who fought to reclaim lands conquered by unbelievers was himself fighting for Christ? Thus, it was in dealing with the Muslim presence in Spain that Western soldiers and theologians first cut their teeth on the idea of holy war. The Reconquista, or “reconquest,” was the training ground for the theological and moral justification of the crusading movement. Like the later crusades, the Reconquista joined military campaigns with holy pilgrimage. In the ninth century, in a thin strip of Christian-held territory in northern Spain, the bones of St. James the Greater were discovered at Santiago de Compostello. The cult of St. James flourished in Europe, and the shrine became a rallying point for warriors who were spurred to liberate the lands they believed the apostle had claimed for Christ. During the first centuries of the Reconquista, the church promoted the war as a just and appropriate reaction to Muslim aggression but did not articulate the kind of spiritual benefits that
would signify a holy war.