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Appeared in Winter 1975, Vol. I, No. 3

In this issue, John H. Cleland continues his provocative study of the theology which justifies the crusade. Having dealt with the underpinnings of the crusading ideal in philosophy, justice and Scripture in Vol. I, No. 2, he now turns to an examination of the ethos of Christian knighthood. The question of what it means to be a soldier of Christ is, of course, an important one in our own secular age. The author — drawing on the notable popes, canonists and theologians of the crusade era — suggests an answer to that question, and in so doing he both illuminates and motivates the modern believer in the value of the cross.

I have been trying to illustrate the emerging moral status of war during the first millennium of Christian history. Well prior to the crusades themselves, there were three separate stages of development: the just war, state warfare in defense of the legitimate interests of a Christian society, and the actual charity of some war. The last stage brings this matter to the brink, and possibly just past the brink, of the crusades. There were, at the same time, successive theological foundations built in support of these stages: a philosophical foundation, a foundation of justice and law, a foundation of Scriptural models. Construction of the fourth and final foundation of crusade theology was begun during the century that immediately preceded the First Crusade, although intimations of it are just below the surface of political Augustinianism. This foundation, the ethos of Christian knighthood, was greatly developed during the 12th century by Bernard of Clairvaux. Presupposing all the foundations built earlier, this foundation may be the strongest weight-bearing element of all for crusade theology.

The development from no war to holy war becomes apparent in the following diagrammatic summary:

Stages in the Theology of War:
(no war theology before 300’s)

  1. The just war
  2. State defense of the faith
  3. Charitable coercion
  4. Holy war

Foundation of Each Stage:

  1. Philosophy (conceived in Augustinian psychology and completed in Thomistic epistemology)
  2. Justice (originated by Ambrose on imperial models; furthered by Augustine’s philosophy of history; embodied in the caesaro-papist politics of early Byzantium; refined in the Scriptural distinctions made by Anselm of Lucca and Gratian)
  3. Scriptural models (holy wars of the OT, including the Maccabean development; intimations of apocalyptic struggle; pilgrimage and sacrifice for Christ — based mainly on Augustinian and Bernardian interpretations)
  4. Ethos of knighthood (pilgrimage, sacrifice; baptism of arms for deliverance of the Church and the Holy Land — hinted at by Augustine; brought to fruition by the reform papacy of the 11th and 12th centuries, chiefly by Pope Gregory VII; climaxed by Bernard of Clairvaux)


Carl Erdmann’s thesis, that the driving force of the crusades derived from “the Church’s gradual admission from about A.D. 1000 of the German warrior ethos into the orbit of Christianity,” (1) is hard to quarrel with. We can see the phenomenon beginning in the activities of the reform papacy of the 11th century. Leo IX (1049-54) was the first pope to conduct wars on directly religious grounds, in the defense effort he masterminded against the Norman invaders of Southern Italy. Alexander II (1061-73) supported military efforts against Moslems in Spain and William of Normandy’s conquest of England. The theological historian Bernard McGinn, in a splendid short overview of crusade history, credits the alliance between the reform papacy and the warlike Normans as “the most significant single factor in the triumph of the idea of holy war in the period from 1050-1100.” Describing the religious legitimacy given to Norman expansion by the popes after 1059 and the Norman military support of the papacy against the German Emperor, McGinn concludes:

From being the objects of a holy war, the Normans overnight became its most fervent proponents. . . . Their religious motivation was real and frequently quite fervent. The fact that it was unalterably mixed with motivation of a much different nature and almost always coincided with enlightened self-interest, is merely an indication of the limits which the baptism of knighthood respected all over Europe (with individual exceptions, of course). (2)

The pope who did more than all others to draw the warrior class of Europe around the Church, in a cordon of defense, was Gregory VII (1073-85). In his successful effort to establish this class as militia sancti Petri, directed by St. Peter’s successors in Rome, it may be said that the Church recognized that war might be justified in principle, and, indeed, she introduced the notion of justice into warfare. (3) Gregory VII, unlike some other popes, never led troops into battle. But in spirit he may have been the most warlike man ever to sit upon the throne of St. Peter. There is no evidence that he personally thirsted for blood. The evidence rather shows that he was so totally convinced of the absolute justice of his policy of reforming Church practices and, as the first step in that process, in ripping ecclesiastical control and appointive power out of the hands of secular princes, that he flinched at no honorable means of crushing his opponents. He considered war and also spiritual sanctions honorable means of doing that.

Medieval schoolmen of more delicate sensibilities concurred. For example, a great humanist of the 12th century renaissance, John of Salisbury, wrote this:

But what is the office of the duly ordained soldiery? To defend the Church, to assail infidelity, to venerate the priesthood, to protect the poor from injuries, to pacify the province, to pour out their blood for their brothers (as the formula of their oath instructs them), and, if need be, to lay down their lives. The high praises of God are in their throat, and two-edged swords are in their hands to execute punishment on the nations and rebuke upon the peoples, and to bind their kings in chains and their nobles in links of iron. But to what end? To the end that they may serve madness, vanity, avarice, or their own private self-will? By no means. Rather to the end that they may execute the judgment that is committed to them to execute; wherein each follows not his own will but the deliberate decision of God, the angels, and men, in accordance with equity and public utility. . . . (4)

In early medieval Europe, as Dawson pointed out, there were two dominant societies and two cultures: the peace society of the Church and the war society of the feudal nobility and their following. Dawson said:

The vital problem of the tenth century was whether this feudal barbarism was to capture and absorb the peace society of the Church, or whether the latter could succeed in imposing its ideals and its higher culture on the feudal nobility, as it had formerly done with the barbarian monarchies of the Anglo-Saxons and the Franks. (5)

The peace of God and the truce of God were two of the Church’s formal attempts to cut the slaughter by restricting it. These attempts to enforce peace came out, even, in Pope Urban’s original invocation of the crusades:

Oh race of the Franks, we learn that in some of your provinces no one can venture on the road by day or by night without injury or attack by highwaymen, and no one is secure even at home. Let us then re-enact the law of our ancestors known as the Truce of God. . . . And now that you have promised to maintain the peace among yourselves you are obligated to succour your brethren in the East, menaced by an accursed race, utterly alienated from God. The Holy Sepulchre of our Lord is polluted by the filthiness of an unclean nation. Recall the greatness of Charlemagne. O most valiant soldiers, descendents of invincible ancestors, be not degenerate. Let all hatred depart from among you, all quarrels end, all wars cease. Start upon the road to the Holy Sepulchre to wrest that land from the wicked race and subject it to yourselves. (6)

Pope Eugene III’s call for the Second Crusade, in 1145, puts slightly more emphasis on the defense of the whole Christian East, which he joins to the particular well-being of the Holy Land.

How much our predecessors the Roman pontiffs did labor for the deliverance of the oriental church, we have learned from the accounts of the ancients and have found it written in their acts. For our predecessor of blessed memory, Pope Urban, did sound, as it were, a celestial trump and did take care to arouse for its deliverance the sons of the holy Roman church from the different parts of the earth. (7)

Bernard of Clairvaux during three periods of his life showed himself favorable to armed combat. He acted as a layman, then as a monk, finally, and above all, as an abbot over a period of more than 40 years, from 1111 to 1153. Having said that, however, I think it is still possible to agree with his 20th century biographer Father Leclercq that Bernard was also a great man of peace. Leclercq points out that it was an age of the most bloody-minded violence: psychological violence, armed violence, and economic violence based on the emergence of large-scale avarice in Western Europe. In the teeth of all this violence Bernard preached humility as the great virtue; he opposed it to every vice of his age. He never wavered in the conviction that a religious vocation is superior to the call to arms. And he emphatically forbade his monks to set out for the crusades on the ground that even this religious way of fighting for Christ, although not reserved for knights alone, was beneath the vocation of spiritual combat the monks had sworn themselves to. Leclercq says this:

By the fact that he recruited a peaceful army of thousands of cistercian monks and favoured the other monastic and canonical orders, he proved himself to be the greatest nonviolent leader of his day. . . . Bernard multiplied houses of peace where people from every social rank, especially young knights, were brought together in a common refusal to take up arms. (8)

Underneath those real spiritual virtues, and tightly controlled by them, lay the instinct of a warrior. Here are extracts from a long letter Bernard wrote to the leader of the Knights of the Temple (or Templars), the order of soldier-monks for whom Bernard had written the rule.

To Hugh, soldier of Christ and master of the chivalry of Christ, Bernard of Clairvaux, abbot only by name: fight the good fight. . . .

I say that this is a new sort of chivalry, unknown through the centuries, because it tirelessly wages an equal and double war both against flesh and blood and against the spiritual forces of evil in the other world. To resist bravely a bodily enemy with bodily force — this I judge to be neither remarkable nor rare. When a strong soul declares war against vice or demons, this too I would not call remarkable, although certainly laudable, since the world is filled with monks. However, when a man of both types powerfully girds his sword and nobly distinguishes himself by his cuirass, who would not consider this, which clearly has hitherto been unknown, worthy of all admiration? . . . He whose life is Christ, and for whom death is profit, what should he fear in life or death? He stands faithfully and willingly for Christ; but he would much prefer disembodiment so as to be with Christ. . . . The danger or the victory of the Christian is determined by the intent of the heart rather than the outcome of the battle. If the cause for which one fights is good, the battle cannot go badly; so also its end shall never be considered good when the cause is not good and the intention which preceded it not just. . . . Truly, when he kills a criminal, he commits not homicide but, as I would call it, malicide, and clearly he may be considered the avenger of Christ in those who do wrong, and the defender of Christians. . . . The point is not, of course, that pagans ought to be killed, if by some other means or in some other fashion they could be repressed from their extreme harrassment and oppression of the faithful. Now, however, it is better that they be killed than to allow the rod of the sinners to stand over the fate of the just, lest the just also should extend their hands toward iniquity. . . . Let therefore the nations who wish for war be scattered, let those be cut down who disturb us. Let all who do iniquity be extirpated from the city of the Lord — those who sought to rob the Christian peoples of the inestimable riches preserved in Jerusalem, to profane the holy places, and to hold in inheritance the sanctuary of the Lord. . . . Hail, therefore, holy city, whom the Most High sanctified as a temple to Himself, so that in you and through you so great a generation might be saved. Hail, city of the great King . . . I say that you are a good land; you received in your most fertile womb a heavenly seed from the treasury of the Father’s heart and have brought forth a great harvest in the celestial progeny of martyrs. (9)

Those words burn modern ears. But the theology they represent is a rich one. It is a theology of controlled, aggressive, crusading warfare. It is a theology that thinks with its mind and not with its blood. But the blood is there.

The saint’s cooler biographer Leclercq notes, however, that Bernard:

imagined, not without some illusion, that the crusader was going to be a voluntary penitent whose sole preoccupation was going to be his own personal salvation and eternal happiness. (10)

Such illusion, of course, is worthy of consideration. Joinville, in his book about the Seventh Crusade — led by St. Louis IX of France — describes the difference between an ordinary knight and the kind who has put his prowess in Christ’s service. He quotes “the great King Philip” as to the difference between a valiant (preux) man and a right worthy man (prud’homme):

For there are many valiant knights in Christian lands, and in the lands of the Saracens who never believed in God nor in His mother. Whence I tell you, said he, that God grants a great gift and a very special grace, to the Christian knight whom He suffers to be valiant of body, and at the same time keeps in His service, guarding him from mortal sin. And the knight who thus governs himself should be called right worthy because that prowess come to him by the gift of God. And those of whom I spoke before may be called valiant because they are valiant of their body, and yet neither fear God nor are afraid of sin. (11)

The Christian faith of the knights and others who went crusading to the Holy Land did not arise principally from any deep understanding of crusade theology, though some instinctive grasp of that theology may be presumed. Each man did whatever he did because of the sort of person he was inside. But I think the sort of person he was inside was reinforced for the better by the presumably efficacious prayer that man’s Lord had expressed more than 1000 years earlier, the night before He died: “I am not praying for the world, but for those you have given me. . . . I am not asking you to remove them from the world. . . . As you have sent me into the world on your errand, I have sent them into the world on my errand” (John 17:9-18). Can one of Christ’s errands be to wage aggressive, crusading warfare and to kill? The answer of many of the greatest saints, fathers, doctors, theologians, canon lawyers, and popes of Catholic Christianity is emphatically yes: for the right reasons, at the right time, in the right way, with the right intentions.



  1. E.O. Blake, The Formation of the Crusade ‘Idea,’ in the Journal of Ecclesiastical History XXI (Jan., 1970), p. 12.
  2. Bernard McGinn, The Crusades (Morristown, N.J.), p. 7.
  3. H. Daniel-Rops, Cathedral and Crusade (London, 1957), p. 276.
  4. The Portable Medieval Reader, assembled by J. Ross and M. McLaughlin (New York, 1971), p. 90.
  5. Christopher Dawson, The Making of Europe, pp. 228-9.
  6. Roland H. Bainton, Christian Attitudes Toward War and Peace, pp. 111-12.
  7. The Papal Encyclicals, ed. A. Freemantle (New York, 1956), p. 67.
  8. Jean Leclercq, Saint Bernard’s Spiritual Attitude to War (1972) in Studies in Medieval Cistercian History, III, ed. Bernard McGinn, p. 7.
  9. The History of Feudalism, ed. D. Herlihy (New York, 1970), pp. 288-98.
  10. Leclercq, p. 21.
  11. Jean de Joinville, Chronicle of the Crusade of St. Lewis (New York, 1958), p. 276.