The Early Church
In beginning an examination of the development of the doctrine of the Just War theory with Ambrose, one has to acknowledge the received tradition with which Ambrose worked. Was there no pre-Ambrosian Just War theory within Christianity? If not, from where did Ambrose draw his framework for his thought? With any examination of Christian doctrine one must start with the teachings of Jesus as outlined in the New Testament. In reading the New Testament the reader is left with no clear decision as to whether the use of force is ever just. Bainton argues that “The attitude of the Gospels… was neutral.” ‘Neutral’ would suggest that they had nothing to say on the subject, however, the New Testament did have things to say about the use of force.
“’Put your sword back in its place,’ Jesus said to him, ‘for all who draw the sword will die by the sword.’” (Mtt 28:52).
With his rebuke of Peter did Jesus repudiate the use of force for all his followers? Further;
“If anyone strikes you on the right cheek, turn the other also… I say to you, love your enemies and pray for those who persecute you.” (Matt 5:39,44).
A seeming repudiation of violence. However, in Luke we read;
“But now, the one who has a purse must take it, and likewise a bag. And the one who has no sword must sell his cloak and buy one.” (Luke 22:36).
Rather than the attitude being neutral I would argue the attitude of the New Testament is ambiguous. It is possible to support a pacifist position from the New Testament, indeed “Frequent attempts have been made throughout subsequent Christian history to claim that because of this teaching and example Christians must be “pacifist” and repudiate all use of violence against other persons.” However, just as frequently attempts have been made to use New Testament texts as justification for war;
“If worldly rulers call upon them to fight, then they ought to and must fight and be obedient, not as Christians, but as members of the state… This is what St. Paul wrote to Titus when he said Christians should obey the authorities.”
The question of the raising of arms in defence or otherwise “to our knowledge… was not raised” in the time of the writing of the New Testament. The texts used to either justify or condemn violence were responses to specific situations and questions raised. In a newly developing Church (or what could conceivably be called a sect) questions were being dealt with as they arose. The only book of the New Testament that talks overtly of war is the book of Revelation. The situation in which this book was written “emerged after the death of Paul, when the Roman government intensified its persecution of Christians.” This was not an earthly war but a war in which “a mighty angel took up a stone like a great millstone and threw it into the sea, saying, ‘With such violence Babylon the great city will be thrown down.’” (Rev. 18:21). This was an eschatological war with Babylon representing Rome to give these early Christians hope. Despite all this discussion the New Testament stance remains ambiguous because war was never an option or a question for the small number of Christians. They do “not comment upon the frontier wars fought by the Romans. From Tiberius to Nerva there were not in fact so many of them, and Britain, one of the main centres of fighting, must not have been even a name to many of the Christians of the eastern Mediterranean.” The social and political situation of New Testament Christianity as a sect of no real regard led directly to its ambiguity in relation to the concept of war and violence. Therefore the Christian position at this time could be seen as one of pragmatism.
Being so close to the time of Jesus “the early Church is frequently regarded as the best qualified to interpret the mind of the New Testament.”  At the end of the first century CE the Christian Church has no particular standing in the society of the Roman Empire, by the time of Augustine in the late fourth century CE Christianity is the religion of the Empire. The theology of militarism was addressed during the first part of this period (up to Constantine) but it was far from the overriding concern. “Christian communities were “busy growing” during the persecutions, and intellectual discussions were focused on the Trinitarian and Christological heresies.”
The first writer to address the subject of war and military service was Justin Martyr in approximately 138CE, in this he quotes the Old Testament prophecy: “nation shall not lift sword against nation nor ever again be trained for war.” (Isaiah 24:4). and goes on “You can be convinced that this has happened… We who used to kill one another, do not make war on our enemies.”
This thinking is further developed by Tatian (c160CE), “I do not want to be an emperor, I do not want wealth, I refuse military office.” Similar feelings are offered by Athenagoras (c177CE), “How could anyone accuse of murder and cannibalism men who, as they well know, cannot bear to see a man killed even if killed justly… We, thinking that to watch a man being killed is practically equivalent to taking life…” The earliest Christian writers of this period seem to abhor violence in any form and reject military service.
The Roman writer, Celsus (173CE) criticises Christianity;
“If all men were to do the same as you there would be nothing to prevent the king from being left in utter solitude and desertion and the forces of the empire would fall into the hands of the mildest and most lawless barbarians.”
Celsus supports the view offered by Justin, Tatian and Athenagoras in acknowledging that “most Christians refused military service and hence were unwilling to do their part in protecting the empire.” On this evidence a fairly concrete conclusion can be reached that Christians did not participate in military service much less a war. But how far is this because of the social situation? Up to this point Bainton notes that “The expansion of Christianity had taken place chiefly among civilians in the urban centres. Few as yet were converted while in the army.” This thinking is echoed by Tooke; “Jews, and therefore Christians, with whom they were generally identified by the Empire, were exempt from military service.” Until 170/180CE Christians were generally outside of the sphere of military service, therefore, along with the writings the practice of the early Christians was pacifist. This may have been a conscious ideology on the part of some (especially the writers) but for others it is more likely to have been a chance of social circumstance (they were not born into a section of society that demanded a response to war or military society), because military service was not an option for most Christians they did not go to war and could, therefore, be considered pacifists (certainly in practice, if not also in ideology). Unfortunately the writings of “average” Christians have not survived (if there ever were any) and so we are left to draw our own conclusions. The conclusion that it was their position of social circumstance rather than choice that determined attitudes to war and military service seems to be supported in the next century of Christian thinking and practice.
There is the suggestion that the early Christians’ aversion to military service “arose from the danger of idolatry because the deified emperor was the commander in chief of the army and the officers were required to conduct sacrifices at his altar.” However, as the writings of the early Church Fathers are read it is evident that “idolatry is little mentioned; it is the bloodshed which was foremost in the mind,” as Bainton notes this practice of idolatry “was true only of officers and not privates.”
As Christianity spread soldiers and families of soldiers would have been converted. In the decade in which Celsus wrote we see an anomaly in the Christian pacifist attitude. In 173CE we have our first evidence of Christians in the army, in the Thundering Legion under Marcus Aurelius. Eusebius reports this story in his History of the Church (323-324CE) as does Tertullian in his Apology (c200CE);
“…by examining the letters of Marcus Aurelius… in which he bears testimony that Germanic drought was removed by the rains obtained through the prayers of the Christians who chanced to be fighting under him.”
Even if this is a tradition that has been exaggerated it shows that there were Christian soldiers in the Thundering Legion. “From that day forward the evidence of Christians in the ranks increases.” There were Christians in the army until the time of Diocletian at the beginning of the fourth century when he purged the army of Christians. “This suggests that though there were Christians in the army they were not very many in number; no commander can afford to eliminate a large number of his troops.” It would seem from this evidence that over a century a significant minority of Christians involved themselves in military service. It has been argued that someone could be a soldier at this time and not take a life. “This sounds fantastic but it was not so during the Pax Romana, when peace prevailed from Hadrian’s Wall in Scotland to the Euphrates save for skirmishes on the frontier. Under such circumstances the army was engaged in police work, fire protection, road maintenance, and much of what we call public works.” This would seem to be supported in the Canons of Hippolytus where military service was allowed but warfare rejected; “A soldier of the civil authority must be taught not to kill.” In this way, even though the attitude of Christians to military service had changed, the obligation not to kill carries on. Thus the social conditions under the Pax Romana seemingly made it increasingly acceptable for a Christian to serve in the army, although possibly under certain restrictions.
However, the Pax Romana did not extend throughout the Empire. In the same area of the Empire as the raising of the Thundering Legion (Meletine) “early in the fourth century when a persecuting emperor attempted to enforce idolatry, the Armenian Christians took up arms and defeated him.” Bainton argues that “These examples indicate a continuous tradition of military service on the part of Christians on the eastern frontier.” Further “The results indicate that pacifism best flourished within the interior of the Pax Romana and was less prevalent in the frontier provinces menaced by barbarians.” Christian attitudes to war were determined by the social and political circumstances; “Where the danger was more acute the reservations were relaxed.” Pacifism flourished in the Pax Romana while in the exterior regions pragmatism and necessity it was the exception.
Christian practice toward warfare and military service therefore underwent a transition. The same cannot be noted in the writings of the Church Fathers. We read from Clement of Alexandria that “We do not train women like Amazons to be manly in war, since we even wish men to be peaceable.” Clement’s contemporary Tertullian was equally opposed to war and military service; “One soul cannot be due two masters- God and Caesar… For albeit soldiers had come unto John, and had received the formula of their rule, albeit, likewise, a centurion had believed, still the Lord afterward, in disarming Peter, unbelted every soldier.” No mention of the influence of the Old Testament has yet been made, this is not to suggest that either, the Old Testament is quiet on this subject, or that the early Church Fathers were ignorant of it. Rather, Tertullian “was aware that the Old Testament sanctions war (even wars of aggression)… for Tertullian, Jesus’ disarming of Peter revoked this sanction.” It is fair to say that this reflected the general attitude of the Early Church fathers; Jesus had taught a higher law which fulfilled and superseded the old law.
Cyprian, Minucious Felix, Irenaeus and Arnobius echoed the pacifist thoughts of Tertullian. Perhaps the most eloquent writer of this time was Lactantius; “Thus it will be neither lawful for a just man to engage in warfare.” Ferguson translates this last sentence: “And so it will not be lawful for a just man to serve as a soldier.”
Thus it would seem that during this period the Church Fathers had more to write against military service and war than their predecessors had. This is because military service was much more of a possibility for Christians, as Christianity penetrated deeper into society practice became more opposed to ideology. The leaders of the Church were pacifists who saw a Christian’s role with their new status in society to “beseech.. God on the emperor’s behalf.”
Christians were to fight the spiritual war rather than the physical one. Although the Church Fathers remained opposed to war, as the opposition to Christianity decreased they found they were able to take on a role within society to pray for the Emperor- something that perhaps would have been unthinkable during the times of persecution.
In spite of the changing attitudes to war and military service in the early Church, it would seem that for Ambrose there was no received tradition within Christianity to talk of a Just War. However, from the experiences of the early Church it is possible to argue that as Christianity became more accepted in society ideology and practice were becoming more opposed in relation to war and military service. In becoming such, it is also possible to argue that one of these would have to give way. Indeed, it was necessary to move Christian military thinking to the next stage. Surprisingly it wasn’t a Christian that tilted the balance.
“And while he was thus praying with fervent entreaty, a most marvellous sign appeared to him from heaven… he saw with his own eyes the trophy of a cross of light in the heavens, above the sun, and bearing the inscription CONQUER BY THIS. At this sight he was struck with amazement, and his whole army also.”
“And so it was that Constantine came to Milvian Bridge, like some Old Testament leader whose army was outnumbered by more than two to one, but whose trust was in the Lord.” In the period of the rule of Constantine the Church went from a sect of society to the official religion of the Empire. This must have seemed a miracle to the early Church, however Constantine had no regard for Christian tradition. He “came into the Church impulsively on his own terms as the result of a battle. He bypassed all the discipline of the Church for the training an initiation of converts. It never occurred to him to question his actions by Christian standards. He did not know what he was doing and the Church did not know what she was getting.” The beliefs of Christianity were reinterpreted in the light of the “conversion” of Constantine. Previously the Church Fathers had repudiated war and military service, now Eusebius was talking of Constantine’s seizure of power as “not the war of an adventurer, but the crusade of a saint.” The change in the political and social conditions of the Christians had changed their teaching. For almost three centuries the Christians had been a peculiar people within the Empire, now they were the mainstream, they had been outside of society in their refusal to fight, now “The faith of the Church… was not the same as the faith that had withstood the imperial cult throughout the centuries… A transformed Christianity became the imperial cult by any other name.”
With legitimisation of military service and war the new Christian hierarchy had to develop teachings on the rights and wrongs of war. Previously it was wrong, Origen had countered Celsus” charge that Rome would be destroyed if all became Christian by saying that;
“If, according to Celsus’s proposition, all the Romans were to be converted they will by praying overcome their enemies- or rather they will not make war at all, being guarded by the Divine Power, which promised to save five whole cities for the sake of fifty righteous men.”
Now that this foreseen time was a reality, praying was no longer an option The Church fathers and Constantine preferred the justification of force. The Empire was now seen as a vehicle for the propagation of the faith, it, therefore, had to be protected and served. The ambiguity and indifference of the Church to matters of war needed to be challenged and modified.
Eusebius began this challenge in his History of the Church and Life of Constantine. War is here glorified and legitimised to serve the purposes of God. “And then stretching out His right hand for requital of His enemies, He eliminated them with a single rod, avenging himself with heaven-sent blows.” It was against this background that Ambrose began to write. He had received little or nothing in Christian tradition up until this point and so had to begin a re-examination of war and military service. He had to continue the work begun by Eusebius in legitimising war in light of the “conversion” of Constantine. Christianity was no longer a sect of no real import, it was the religion of the Empire and had to defend both its place and the place of the Empire.
 R. Bainton Christian Attitudes Toward War and Peace (Hodder & Stoughton, 1960) p53.
 R.G. Jones Groundwork of Christian Ethics (Epworth Press, 1984) p83.
 Luther Whether Soldiers , too, Can be Saved IX:9
 Bainton (Hodder & Stoughton, 1960) p55
 Ibid. p56.
 J. Ferguson The Politics of Love The New Testament and Non-Violent Revolution (James Clark, ND) p55.
 R. Bainton Christian Attitudes Toward War and Peace (Hodder & Stoughton, 1960) p66.
 J.D. Tooke The Just War in Aquinas and Grotius (SPCK, 1965) p1.
 1 Apology 39 cit Ferguson The Politics of Love p57.
 cit Ibid. p57.
 cit Ibid. p58 Emphasis added.
 cit. Bainton Christian Attitudes Towards War and Peace p68.
 R. Wilken The Christians As The Romans Saw Them (Yale U.P. 1984) p117
 Christian Attitudes Towards War and Peace p68.
 The Just War in Aquinas and Grotiusp1.
 R. Bainton Early Christianity p53.
 J.Ferguson The Politics of Love p65.
 R. Bainton Early Christianity p53
 Apology Ch. V
 Bainton Christian Attitudes Towards War and Peace p68.
 Ferguson The Politics of Love p63.
 R. Bainton Early Christianity (Krieger Publishing Co. 1960) pp54-55.
 cit. Ibid. p152.
 Christian Attitudes Towards War and Peace pp70-71.
 Ibid. p69.
 Bainton Early Christianity p55.
 cit. Ferguson The Politics of Love p58.
 On Idolatry (19)
 R. Gill A Textbook of Christian Ethics p300.
 The Divine Institutes (Book V Chap XX)
 Politics of Love p62.
 Tertullian Apology (XXX)
 Eusebius The Life of Constantine (CL.XXVII)
 A. Kee Constantine Versus Christ (SCM Press Ltd. 1982) p17.
 J. Bulloch Pilate to Constantine (St. Andrew Press, 1981) p315.
 cit. A. Kee Constantine Versus Christ p138.
 Ibid. p158.
 cit. Ferguson The Politics of Love p59.
 cit. A. Kee Constantine Versus Christ p122.