“By common consent, Augustine is the fountainhead of a tradition almost ubiquitous in medieval thought.”
Augustine is seen by most people as the first and foremost authority of the legitimisation of war for Christians. Gill has observed that “it is evident that Augustine reflected the transition of Christianity to a more church type position in society. He remained uneasy about this position and was well aware of Christianity’s pacifist heritage, but he did still sanction the full participation of Christians in war.” Having examined the contribution of Ambrose to the doctrine of just war it is clear that he, not Augustine, was the first authority on the legitimisation of war. In examining the writings of Augustine it becomes evident that he followed the framework that had been adopted by Cicero, and then Ambrose. On reading the account of his life this comes as no great surprise, Schaff notes in the Prolegomena to Augustine’s works that, “He received baptism from Ambrose in Milan on Easter Sunday, 387…” At this crucial time in his life as Christian, Augustine was under the tutelage and influence of Ambrose, it is without doubt that he would have become conversant with the thoughts of Ambrose. It is, however, quite conceivable to still call Augustine the foremost authority. As Markin notes;
“By the time Augustine began to write, his views on the legitimacy of waging war- with or without the sophisticated intellectual structure in which they became incorporated in his exposition- would have been widely accepted among Christians… What medieval canonists and theologians found in Augustine was a quarry of authoritative texts to quote according to need.”
As the foremost authority it is important to the Christian to understand the influences on his thinking. Throughout the course of this chapter Augustine’s organisation of his thoughts on war will be examined. It will also see to what extent Augustine drew on the received tradition, reflected his own socio-political situation and developed his own thoughts on the just war. To do this it is necessary to focus on different aspects of his just war thinking- the justness of war, the authority under which it is waged, the purpose, conduct and causes of a just war, the need for it to be a last resort, and finally, the question of the participation of the clergy.
Augustine’s influence on the thought of writers discussing the just war will then be examined, this will serve to highlight how Augustine has come to be regarded as the ‘fountainhead of tradition’. Following a short discussion of the intervening years the next section will focus on the writings of Thomas Aquinas. He is commonly regarded as one of the foremost authorities on the just war. Indeed, school children today are taught that he, rather than Augustine established the classical just war theory, one textbook states;
“Thomas Aquinas drew up the Just War principle.”
This section will examine his teachings and how they relate to the writings of Augustine; and if this foremost place in just war thinking is accurate. Tooke has argued that;
“Aquinas’s direct teaching… is slight and unoriginal. Devised more or less wholesale from Augustine… its is abstract and theoretical, and inspired by no personal emotion or thought.”
The same aspects (as applicable) of Aquinas’ just war teaching will be examined to see if this is, indeed true, or if as Jones argues, much more credit must go to Aquinas as he“put Augustine’s original thinking into much more refined shape, and produced three criteria.”
The Justness of War
In discussing the justness of war Augustine begins the new development of using the New Testament to defend his position. Although the Old Testament was referred to (“Like Ambrose, his mentor at the time of his conversion, Augustine shows himself ready to defend Old testament militarism…”), the New Testament is his focus;
“Otherwise John, when the soldiers who came to be baptised asked, What shall we do? would have replied, Throw away your arms; give up the service; never strike, or wound, or disable any one. but knowing that such actions in battle were not murderous, but authorised by law, and that the soldiers did not thus avenge themselves, but defend the public safety, he replied, ‘Do violence to no man, accuse no man falsely, and be content with your wages.’…Again, in the case of the centurion who said, ‘I am a man under authority, and have soldiers under me and I say tone, Go, and he goeth; and to another, Come and he cometh; and to my servant, Do this and he doeth it,’ Christ gave due praise to his faith; He did not tell him to leave the service.”
In adopting this position Augustine is perhaps reflecting a development in Christian thought. The Christian thinkers were now comfortable (so far removed from the time of Jesus and the early Church’s interpretation) in reinterpreting the words of Jesus to defend their position (or so it would seem). The justness of war was really not a question to be dealt with- as noted before that argument had been won by Augustine’s predecessors. Though why Augustine felt it necessary to elucidate on these writings can be seen when one examines the political situation of his day;
“He was the great apologist of the Christian Church at the time when it had just allied itself to the State, and his acceptance of Christian warfare was no doubt part of his defence against the charge that pacific Christianity had been responsible for the downfall of the Roman Empire.”
Living between 354CE and 430CE Augustine lived through the Empire being split into two (395CE), the regular raids of barbarian tribesmen, and Rome, itself, being sacked (410CE). The Empire that had flourished with ‘pagan’ religions was now in decline under the influence of the Christian religion. It must have seemed a time of upheaval and confusion to all those involved. Indeed, in the Prolegomena to Augustine’s works it is noted that
“The evening of his life was troubled by increasing infirmities of body and by the unspeakable wretchedness which the barbarian Vandals spread over his country in their victorious invasion, destroying cities, villages, and churches, without mercy, and even besieging the fortified city of Hippo.”
In this situation it is easy to see why Augustine felt it necessary to promote Christianity and the justness of war- in recalling the words of John the Baptist and Jesus, himself, Augustine is creating the impression that from the beginning Christianity had been supportive of the army and war, and the charge that they had brought about the fall of the Empire was false.
“A great deal depends on the causes for which men undertake wars, and on the authority they have for doing so; for the natural order which seeks the peace of mankind, ordains that the monarch should have the power of undertaking war if he thinks it is advisable…” 
In a further reference to the New Testament we find Augustine arguing that;
“To take the sword is to use weapons against a man’s life, without the sanction of the constituted authority.”
Rather than the underlying theme of authority that we find in Ambrose we find this thinking formalised into an outright condition for just war. Augustine also carries on Ambrose’s theme of sedition, though again in a much more forthright language. Ambrose had said;
“We should be doing harm, not good, to another if we gave him money to aid him in plotting against his country.”
Augustine now said;
“Since, therefore, a righteous man may be under an ungodly king, may do the duty belonging to his position in the State in fighting by the order of his sovereign,- for in some cases it is plainly the will of God that he should fight, and in others, where this is not so plain, it might be an unrighteous command on the part of the king, while the soldier is innocent, because his position makes obedience a duty…”
Taken together there is still no hard and fast rule concerning sedition, but using the words of Augustine, when he says that one must obey an ‘ungodly’ sovereign it surely must extend to not rebelling against this legitimate authority. This treatment of the concern of serving under an ungodly sovereign reflects the changed social and political situation of Augustine. In the time of the pre-Constantinian Church this would not have been a problem for the Church Fathers- because all war was forbidden. The same would have been true in the intervening time because the sovereign/ ruler with which the Christians had to do was the Roman Emperor- who was himself, for the most part, Christian. With the changing times and the breaking up of the Roman Empire it would seem likely that more and more Christians were finding themselves in countries or provinces with ungodly (i.e. not Christian) rulers.
It is also, perhaps, a reflection of the disputes he found himself in with the Donatists.
“Their (the Donatist’s) major complaint against their fellow Christians was on the question of the readmission into the Church of those who, in times of persecution, had abandoned their faith and been apostate. Catholics were generally willing to readmit them after some disciplinary probation; Donatists were not.”
By ‘apostasy’, what is generally meant was the offering of sacrifice to other gods. Writing against them, Augustine could be defending the actions of these ‘apostates’ by using the argument that their position made “obedience a duty.” This is a possibility, but one which flouts the martyrdoms of numerous Christian in the previous centuries. Much more likely is the numerous countries Christians now found themselves in.
The major development in this aspect of just war thinking was the acknowledgement that God (or his delegated authorities- i.e. the Church) was also a legitimate authority to declare war;
“When war is undertaken in obedience to God, who would rebuke, or humble, or crush the pride of man, it must be allowed to be a righteous war…”
Augustine justifies this thinking from the Old Testament;
“Moses… we love and admire, and to the best of our power imitate… which actions of Moses (the slaying of the Egyptian and war) were in one case prompted by the zeal of the future champion of his people, and in other cases commanded by God.”
Also, in this development, can be seen the background of the schism with the Donatists. When Augustine became Bishop of Hippo (396CE) it had been prevalent for eighty five years, and he “felt that it was impossible passively to accept such a situation of deadlock.” In January 412CE, with the sanction, and encouragement, of Augustine the Emperor Honorius sanctioned the use of force against the Donatists (as Marcarius had done in 347CE). Christians who had once been persecuted and coerced, were now, themselves, persecuting and coercing dissenters. “Non-violence had been appropriate to the age of the Apostles, now, in these ‘Christian times’, there is prophetic sanction for the use of force on Christ’s behalf.” One feels that such a course of action would have seemed abhorrent to Ambrose (even with his own use of the Old Testament), but in adapting his thinking to his circumstances Augustine was developing thinking on the just war and laying the foundation for religious wars in the centuries to come.
The Purpose of a Just War
The important purpose of a just war remains the same for Augustine as it was for Ambrose;
“Peace should be the object of your desire; war should only be waged as a necessity, and waged only that God may by it deliver men from the necessity and preserve them in peace. For peace is not sought in order to the kindling of war, but war is waged in order that peace may be obtained. Therefore, even in waging war, cherish the spirit of a peacemaker, that, by conquering those whom you attack, you may lead them back to the advantages of peace; for our Lord says ‘Blessed are the peacemakers; for they shall be called the children of God.’”
Here, then, is no seeming development, but in responding to the individual needs of Boniface Augustine elucidates on the writings of Ambrose by suggesting ways in which the individual soldier may have this just purpose in war.
The Conduct of a Just War
In this area of just war thinking Augustine states;
“For, when faith is pledged, it is to be kept even with the enemy against whom the war is waged.”
Recalling the similar words of Ambrose on justice and faith;
“It must even be preserved in all dealings with enemies.”
In a discussion remarkably similar to Ambrose’s of Elisha in which he says;
“it was seemly to spare an enemy, and to grant his life to an adversary when he could have taken it, had he not spared it.”
Augustine relates similar counsel to Boniface;
“Let necessity, therefore, and not your will, slay the enemy who fights against you. As violence is used towards him who rebels and resists, so mercy is due to the vanquished or the captive, especially in the case in which future troubling of the peace is not to be feared.”
However, in developing this theme of conduct in war Augustine discusses much further the attitudes which must be absent in the conduct of a war;
“The real evils in war are love of violence, revengeful cruelty, fierce and implacable enmity, wild resistance, and the lust of power, and such like.”
This gives the reader the basis of Ambrose (and, indeed, Cicero) but takes it a step further. Rather than a result of the social and political context of Augustine, this is the next logical step in the thought and discussion of the conduct of a just war- putting flesh on the bare bones of Ambrose- so to speak.
The Just Cause of War
For Augustine “Apart from the direct command of God, an injustice or wrong caused by the enemy is the only sufficient justification of war.” Augustine gave scant consideration to a war of defence, presumably this is because he saw it as automatically just. For Augustine, there is no long discussion of what individual acts constitute an offence, such as we find in the writings of Ambrose. Reflecting a more precarious social situation, Augustine’s legitimisation of war on the basis of cause is brief and open to interpretation. In developing and illustrating his thinking of injustice or wrong
“One example of such an injury he gave is that of the refusal of the Amorites to allow free passage through their territory to the Israelites.”
This seems a long way from the war “to bring help one to the other” and to “stop the weak from being oppressed” of Ambrose (see above p.35). However, he does acknowledge, following the discussion of the real evils of war, (see above p.34) that
“…it is generally to punish these things, when force is required to inflict the punishment, that, in obedience to God or some lawful authority, good men undertake wars, when they find themselves in such a position as regards the conduct of human affairs, that right conduct requires them to act, or to make others act in this way.”
In allowing God (or more truthfully the representatives of the Church) the right to declare wars, another cause of a just war is enabled. For what cause do God’s agents declare war?
“The account of the wars of Moses will not excite surprise or abhorrence, for in wars carried on by divine command, he showed not ferocity but retribution, but in righteous retribution, giving to all what they deserved, and warning those who needed warning.”
It would seem from this that the agents of God declares war for the same purpose as man- because of some wrong. It is strange that in both these causes there is the underlying purpose of punishment and retribution. Taken alone this is a departure from the writings of Ambrose, but when examined alongside the purpose and conduct of wars the reader can see the importance of the phrase ‘righteous retribution’. This is a formalisation of the causes and purposes of war given by Ambrose, he may not have mentioned righteous retribution, but what else could the righting of wrongs be called in the Christian tradition, if they needed to be given a name?
The Last Resort
“Peace should be the object of your desire; war should only be waged as a necessity, and waged only that God may by it deliver men from the necessity and preserve them in peace.’”
Here, again, the thinking of Ambrose is formalised into more forthright and straightforward language. Interestingly, however, one can see from the life of Augustine, that this is a principle which affected his practice, and thus, must have seemed very important to him to teach. Henry Chadwick notes, with regard to Augustine’s relations with the Donatists, that;
“He inspired a series of church councils under the metropolitan at Carthage… [Discussion having failed] Augustine knew that the motives which bring men to truth are often complex, and may include elements of fear or self-interest that have to be regarded as a temporary stage towards a full, glad, and willing assent. Moreover, the highest function of penal action is remedial what looks like a deterrent penalty of harsh severity may do good as the offender learns to recognise its justice and beneficial social intention. And had not the Lord in the parable said ‘Compel them to come in’? It was by such reasoning that Augustine’s mind was reluctantly and painfully moved to accept a policy of coercion, understood, however, as paternal correction.”
The Participation of the Clergy
In reading the writings of Augustine the reader would find no comprehensive statement on the participation of the clergy in warfare. There are two possibilities as to why this may be so. The first is that, having sanctioned war against the Donatists, Augustine would have felt hypocritical in forbidding the clergy to participate in war. The second possibility, is that since the time of Ambrose, and before, it had become an accepted fact that the clergy would not participate in war, Augustine felt no need to address this question because this argument had already been won. This second possibility comes to the fore when one reads different parts of Augustine’s writings, in addressing Boniface Augustine discusses the different offices;
“They occupy indeed a higher place before God who, abandoning all these secular employments, serve Him with the strictest chastity; but ‘every one,’ as the apostle says, ‘hath his proper gift of God, one after this manner, and one after that.’ Some, then, in praying for you, fight against their invisible enemies; you, in fighting for them, contend against the barbarians, their visible enemies.”
Because of the acceptance of this practice in the time of Augustine, he felt no real need to include it in his discussion of the practice of war, he referred to it only in passing.
The real development in this area of Christian thinking on war has been referred to earlier. Clergy were now able, in Augustine’s mind, to play an active part in the declaration and sanctioning of warfare.
Between Augustine and Aquinas
Tooke notes that “From Augustine’s time until the twelfth century there were few developments in the doctrine of the just war.” Within this time, while there were writers, such as Yves de Chatres (1040-1116) and Peter Abelard (1079-1142), who considered war they made no significant developments and were “mainly dependent on Augustine.” Even the “most important writer”, Gratian, who first introduced the just war in the scholastic method purely listed “all the objections to the points in question, quoted the traditional answers, mostly from Augustine, and usually added brief conclusions of his own.”
The most significant developments with regard to Christian attitudes to war can be found in its practice. The clergy began to be involved in the government of cities and countries, because of this Bainton notes that;
“Under such circumstances they could scarcely obviate involvement in war. In the days of the invasions even abbots as well as bishops donned armour over their cassocks to repel raiders.”
The Crusades themselves found many churchmen involved in the fighting. They are not treated in this discussion because as Bainton notes the just war and the crusade are inherently different;
“The crusade differed from the just war primarily in its intensely religious quality. The just war, to be sure, was not devoid of religion, and to disregard its conditions would be to incur the displeasure of the gods, but it was fought for mundane objectives, albeit with a religious sanction, whereas the crusade was God’s war.”
Jones goes further when he describes a crusade as “God versus the devil.” The crusades highlight that the prohibition on the participation of clergy in war had broken down. Though, this happened even before they started. The major development in this period with regard to Christian attitudes to war was the growing influence of the Church on affairs of state, and it is against this background that just war thinking finds itself in the same position going into the thirteenth century as it was in the early fourth.
 R. A. Markins “Saint Augustine’s Views on the Just War” in W.J. Sheils (Ed) Studies in Church History. Vol. 20. The Church and War. (Basil Blackwell, 1983) p1.
 A Textbook of Christian Ethics p306.
 P. Schaff & H. Wace (Eds) A Select Library of Nicene and Post-Nicene Fathers of the Christian Church. First Series Vol. I St. Augustine p4
 “Saint Augustine’s Views on the Just War” pp11-12.
 Ann Lovelace & Joy White Beliefs, Values and Traditions (Heinemann, 1996) p73.
 Joan D. Tooke The Just War in Aquinas and Grotius p170.
 Richard. G. Jones Groundwork of Christian Ethics pp87-88.
 Robin Gill A Textbook of Christian Ethics p304.
 Reply to Faustus the Manichean Book XXII:74.
 J.D. Tooke The Just War in Aquinas and Grotius p12.
 P. Schaff & H. Wace (Eds) A Select Library of Nicene and Post-Nicene Fathers of the Christian Church. First Series Vol. I St. Augustine (Wm. B. Eerdmans, 1979) pp5-6.
 Augustine Against Faustus the Manichean Book XXII:75.
 Against Faustus the Manichean XXII:70
Duties of the Clergy Book 1 Chapter XXX:144
 Against Faustus the Manichean Book XXII:75
 Richard G. Jones Groundwork of Christian Ethics (Epworth Press, 1984)p87.
 see Henry Chadwick The Early Church. Revised Edition (Penguin, 1993) pp122-124.
 Augustine Against Faustus the Manichean Book XXII:75.
 Ibid. Book XXII:69.
 Henry Chadwick The Early Church p222.
 see Ibid. p220.
 R.A. Markins “Saint Augustine’s Views on the Just War.” p9.
 Augustine Letters CLXXXIX:6.
 Augustine Letters CLXXXIX:6.
 On the Duties of the Clergy Book I Chapter XXIX:139.
 On the Duties of the Clergy Book III Chapter XIV:86-87
 Augustine Letters CLXXXIX:6.
 Against Faustus the Manichean Book XXII:74.
 Joan D. Tooke The Just War in Aquinas and Grotius p11.
 Ibid. p11.
 Against Faustus the Manichean Book XXII:74.
 Ibid. Book XXII:74.
 Augustine Letters CLXXXIX:6.
 The Early Church pp222-223.
 Augustine Letters CLXXXIX:5
 Joan D. Tooke The Just War in Aquinas and Grotius (SPCK 1965) p12.
 Ibid. p13.
 Ibid. p13.
 R.H. Bainton Early and Medieval Christianity (Hodder & Stoughton, 1965) p53.
 R.H. Bainton Christian Attitudes Toward War and Peace p44.
 Richard G. Jones Groundwork of Christian Ethics p85.