While living abroad in China I began hearing the drum-beat of war. I was there during the Hong Kong crisis and the trade-war. I heard the propaganda of both the CCP and the U.S. And I heard the perspectives of ordinary Chinese people. I listened to proponents of the Just War theory present their case for standing up against the darkness of tyranny with military intervention. And I grappled with how to reconcile Jesus with the pro-war rhetoric that I was hearing. Then the drum-beat of war got put on pause during the pandemic.

I have been intensely focused on studying this subject over the last four years because my soul has been deeply troubled by the trajectory that I have been observing. Both at home and abroad, I am seeing the historical patterns of escalation everywhere. And within the Church, I am not seeing anyone think very deeply on this subject. To be quite blunt, I see almost no one reverentially thinking through how Christians should respond in times of violence. And the result of this is almost certain to be spiritually catastrophic when times of violence fall upon us. So I am working on a series of posts that will address the subject of war.

The question of how Christians should respond to war is not unique to our time. From the very beginning, Christians have been forced to wrestle with this most difficult topic. So I believe this is the best place to begin in addressing this subject.

Biblical References

Here are the most commonly cited Bible passages by early Christian thinkers on the subject of war:

Isaiah 2:3-4 (CSB) – 3 and many peoples will come and say, “Come, let’s go up to the mountain of the Lord, to the house of the God of Jacob. He will teach us about his ways so that we may walk in his paths.” For instruction will go out of Zion and the word of the Lord from Jerusalem. 4 He will settle disputes among the nations and provide arbitration for many peoples. They will beat their swords into plows and their spears into pruning knives. Nation will not take up the sword against nation, and they will never again train for war.

Matthew 5:38–42 (CSB) – 38 “You have heard that it was said, An eye for an eye and a tooth for a tooth., 39 But I tell you, don’t resist an evildoer. On the contrary, if anyone slaps you on your right cheek, turn the other to him also. 40 As for the one who wants to sue you and take away your shirt, let him have your coat as well. 41 And if anyone forces you to go one mile, go with him two. 42 Give to the one who asks you, and don’t turn away from the one who wants to borrow from you.

Matthew 26:52 (CSB) – 52 Then Jesus told him, “Put your sword back in its place because all who take up the sword will perish by the sword.

John 18:36 (CSB) – 36 “My kingdom is not of this world,” said Jesus. “If my kingdom were of this world, my servants would fight, so that I wouldn’t be handed over to the Jews. But as it is, my kingdom is not from here.”

2 Corinthians 10:3–4 (CSB) – 3 For although we live in the flesh, we do not wage war according to the flesh, 4 since the weapons of our warfare are not of the flesh, but are powerful through God for the demolition of strongholds…

Justin Martyr

Justin Martyr (c. 110–165) was a pagan philosopher who converted to Christianity and became a tireless evangelist. He died as a martyr during the reign of Marcus Aurelius.

We who formerly murdered one another now refrain from making war even upon our enemies.

(c. 160, E), 1.176

We used to be filled with war, mutual slaughter, and every kind of wickedness. However, now all of us have, throughout the whole earth, changed our warlike weapons. We have changed our swords into plowshares, and our spears into farming implements.

(c. 160, E), 1.254

Justin Martyr reflects the universal consensus of earliest Christian convictions regarding war, living within the first generation of Christians after the death of the last apostle. He is an excellent source of how Christians thought about war, and views turning from violence to peace even with respect to one’s enemies as one of the marks of Christian conversion.

Justin Martyr’s comments seem to reflect Paul’s theology of the new creation:

1 Corinthians 6:11 (CSB) – 11 And some of you used to be like this. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.

The expectation was for Christians to change from the manner and conduct of the world to that of Christ. And, as with all Christians in his time, Justin Martyr drew this expectation for peace as one of the chief Christian virtues was from Isaiah’s prophecy and interpreted them as being realized at least in some tangible sense presently in the church of Christ.

As we will see with some degree of redundancy, the early Church expected Christians to be peacemakers.

Athenagoras

Athenagoras was “a Christian philosopher of Athens” during the reign of Marcus Aurelius (A. D., 161–180), but is otherwise unknown, not being mentioned by Eusebius, Jerome, or Photius.

We have learned not to return blow for blow, nor to go to law with those who plunder and rob us. Instead, even to those who strike us on one side of the face, we offer the other side also.

(c. 175, E), 2.129

Athenagoras’ obscurity shows just how far-reaching the doctrines of peace were within the early Church. These were not doctrines limited to some ruling elite, but were pervasive throughout the whole Christian Church. And he drew upon Matthew 5:38-42 to affirm that Christians must respond to violence with peace.

Irenaeus

Irenaeus (c. 130–200) was probably a native of Smyrna, where he had been taught by Polycarp (who was the disciple of the apostle John). He eventually settled in Gaul, in the city of Lyons, where he became the bishop.

The new covenant that brings back peace and the law that gives life have gone forth over the whole earth, as the prophets said: “For out of Zion will go forth the law, and the word of the Lord from Jerusalem; and he will rebuke many people; and they will break down their swords into plowshares, and their spears into pruninghooks, and they will no longer learn to fight.” … These people [i.e., Christians] formed their swords and war-lances into plowshares… that is, into instruments used for peaceful purposes. So now, they are unaccustomed to fighting. When they are struck, they offer also the other cheek.

(c. 180, E/W), 1.512

As one of the most influential theologians of the early Church, Irenaeus clearly adopted the prevailing interpretation that Isaiah’s prophecy was realized in the Church. Most importantly, Irenaeus tells how Christians “formed their swords and war-lances into… instruments used for peaceful purposes.” The doctrines of peace were viewed as the necessary mark of all who followed Jesus. He even described Christians as being so transformed by Christ’s doctrines of peace that they are now unfamiliar with warfare, as if the transformation were so complete that they were useless as instruments of war!

Clement of Alexandria

Clement of Alexandria (c. 150–200) was the head of the catechetical school in the church at Alexandria. His most famous pupil was Origen.

It is not in war, but in peace, that we are trained.

(c. 195, E), 2.234

The one instrument of peace is what we employ: the Word alone, by whom we honor God…

(c. 195, E), 2.249

He bids us to “love our enemies, bless them who curse us, and pray for those who despitefully use us.” And He says: “If anyone strikes you on the one cheek, turn to him the other also; and if anyone takes away your coat, do not hinder him from taking your cloak also.”

(c. 195, E), 2.293

An enemy must be aided, so that he may not continue as an enemy. For by help, good feeling is compacted and enmity dissolved.

(c. 195, E), 2.370

His position in the catechetical school of Alexandria makes Clement of Alexandria one of the best representations of early Christian belief, showing just how widely held these doctrines of peace were among early Christians.

First, he carries forward the sentiment previously articulated that Christians are not useful in war because they were trained in peace. Consider just how foreign this sentiment is to the modern Church. We are so accustomed to the Just War theory that many Western Christians are, in fact, familiar with the constructs of warfare!

Second, the doctrines of peace were so transformative in the life of early Christians that even those who would be their enemies could no longer continue to be viewed as their our enemies! And this transformation was empowered by their proactive love of their enemies.

Tertullian

Tertullian (ca. 155–220) was an early Latin father of the church, born Quintus Septimus Florens Tertullianus at Carthage in modern Tunisia. He was the son of pagan parents, who sent him to Rome to study law. There he was converted to Christianity and rejected his licentious mode of life. Returning to Carthage, he gave himself passionately to the propagation and defense of the gospel. Eventually he became disenchanted with the laxity of the Roman Church, and so broke away from them and espoused the rigorous asceticism and enthusiasm of Montanism (continued divine revelation). To this point it is necessary to note that Tertullian maintained that the rule of faith was fixed and immutable, but saw a need for continued supernatural revelation of truth on matters of personal duty and discipline.

About war he commented:

If, then, we are commanded to love our enemies (as I have remarked above), whom have we to hate? If injured, we are forbidden to retaliate, lest we become just as bad ourselves. Who can suffer injury at our hands?

(c. 197, W), 3.45

We willingly yield ourselves to the sword. So what wars would we not be both fit and eager to participate in (even against unequal forces), if in our religion it were not counted better to be slain than to slay?

(c. 197, W), 3.45

God puts His prohibition on every sort of man-killing by that one inclusive commandment: “You shall not kill.”

(c. 197, W), 3.80

“Nation will not take up sword against nation, and they will no more learn to fight.” Who else, therefore, does this prophecy apply to, other than us? For we are fully taught by the new law, and therefore observe these practices.… The teaching of the new law points to clemency. It changes the primitive ferocity of swords and lances to tranquility. It remodels the primitive execution of war upon the rivals and enemies of the Law into the peaceful actions of plowing and cultivating the land.

(c. 197, W), 3.154

Now inquiry is made about the point of whether a believer may enter into military service. The question is also asked whether those in the military may be admitted into the faith—even the rank and file (or any inferior grade), who are not required to take part in sacrifices or capital punishments.… A man cannot give his allegiance to two masters—God and Caesar.… How will a Christian man participate in war? In fact, how will he serve even in peace without a sword? For the Lord has taken the sword away. It is also true that soldiers came to John [the Baptist] and received the instructions for their conduct. It is true also that a centurion believed. Nevertheless, the Lord afterward, in disarming Peter, disarmed every soldier.

(c. 200, W), 3.73

Is the [military] laurel of triumph made of leaves, or of corpses? Is it adorned with ribbons, or with tombs? Is it wet with ointments, or with the tears of wives and mothers? It may be made of some [dead] Christians too. For Christ is also believed among the barbarians.

(c. 211, W), 3.101

Tertullian notes one of the fundamental shortcomings of the Just War Theory, namely, that evil triumphs when we kill because we ourselves become violent. War necessarily transforms otherwise peaceful people into violent ones. This shows an early awareness within the Church that one of the reasons Christians can’t engage in war is because of the change it brings about in them.

Tertullian goes into greater detail in answering why Christians cannot participate in warfare on several grounds: 1) love has displaced hate; 2) war makes people violent; 3) it is better to die than to kill; 4) we can do no harm even to our enemies; 5) God prohibits killing; 6) Christians have been transformed into peacemakers as described by Isaiah’s prophecy; 7) Christians cannot serve both God and State; 8) the victories of war come by the violence of suffering and corpses, which are forbidden Christians; 9) Christians might accidentally kill other Christians.

Origen

Origen (c. 185–251) was one of the most learned—and most original—Christian teachers of his day. For many years, he served as the teacher of catechumens in the church in Alexandria. He was also the most prolific writer of the pre-Nicene church, dictating around 2,000 works. He produced not only doctrinal and apologetic works, but also commentaries on most of the books of the Bible. He also traveled widely, becoming acquainted with Christian leaders throughout the Roman world.

To those who inquire of us from where we come, or who is our founder, we reply that we have come agreeably to the counsels of Jesus. We have cut down our hostile, insolent, and wearisome swords into plowshares. We have converted into pruning hooks the spears that were formerly used in war. For we no longer take up “sword against nation,” nor do we “learn war any more.” That is because we have become children of peace for the sake of Jesus, who is our Leader.

(c. 248, E), 4.558

In the next place, Celsus [a pagan critic] urges us “to help the king with all our might, to labor with him in the maintenance of justice, and to fight for him. Or if he demands it, to fight under him or lead an army along with him.” To this, our answer is that we do give help to kings when needed. But this is, so to speak, a divine help, “putting on the whole armor of God.” And we do this in obedience to the commandment of the apostle: “I exhort, therefore, that first of all, supplications, prayers, intercessions, and thanksgiving be made for all men; for kings, and for all who are in authority.” So the more anyone excels in godliness, the more effective the help is that he renders to kings. This is a greater help than what is given by soldiers who go forth to fight and kill as many of the enemy as they can. And to those enemies of our faith who demand us to bear arms for the commonwealth and to slay men, we reply: “Do not those who are the priests at certain shrines … keep their hands free from blood, so that they may offer the appointed sacrifices to your gods with unstained hands that are free from human blood? Even when war is upon you, you never enlist the priests in the army. If, then, that is a praiseworthy custom, how much more so that—when others are engaged in battle—Christians engage as the priests and ministers of God, keeping their hands pure. For they wrestle in prayers to God on behalf of those who are fighting in a righteous cause, and for the king who reigns righteously… Accordingly, in this way, we are much more helpful to the kings than those who go into the field to fight for them. And we do take our part in public affairs when we join self-denying exercises to our righteous prayers and meditations, which teach us to despise pleasures and not to be led away by them. So none fight better for the king than we do. Indeed, we do not fight under him even if he demands it. Yet, we fight on his behalf, forming a special army—an army of godliness—by offering our prayers to God. And if Celsus would have us “lead armies in defense of our country,” let him know that we do this too. And we do not do it for the purpose of being seen by men or for vainglory. For in secret, and in our own hearts, our prayers ascend on behalf of our fellow-citizens, as from priests. And Christians are benefactors of their country more than others. For they train up citizens and inculcate piety to the Supreme Being. And they promote to a divine and heavenly city those whose lives in the smallest cities have been good and worthy.

(c. 248, E), 4.667, 668

Origen likewise interpreted Isaiah’s prophecy as being realized among Christians and concluded that on this basis the idea that Christians should fight in “just wars on behalf of their nations” was contrary to both the calling and privilege of Christians as God’s royal priests.

Among the standout points Origin makes is the idea that “coming into agreement with the counsels of Jesus” necessarily resulted in “cutting down our hostile, insolent, and wearisome swords into plowshares.” Christians no longer “took up sword against nation”, nor “learned war anymore” because they have “become children of peace for the sake of Jesus.”

Origen expounds at great length on this subject, arguing that all of the express commands of the Lord and his apostles prohibited Christian engagement in war. To this point, even if someone argues that Isaiah’s prophecy has zero realization in the Church, which I think is an indefensible argument, it is impossible to argue that “love your enemy” doesn’t. Modern theologians have added an unbiblical exemption to all these doctrines of peace, arguing that peace might be violated, and the Christian might learn war to overcome evil with violence if they deem the ends justifies the means. There is no evidence that I could find that any early Christians accepted this line of reasoning. In fact, they all universally condemned it as actually rejecting the counsels of Jesus.

Cyprian

Cyprian was bishop of Carthage from about 248 to 258. A vast amount of the correspondence both from him and to him has been preserved. This gives the modern reader considerable insight into church life in the middle of the third century. During the Decian persecution, Cyprian continued his ministry underground. When the Valerian persecution broke out a few years later, however, he was captured and beheaded.

Wars are scattered all over the earth with the bloody horror of camps. The whole world is wet with mutual blood. And murder — which is admitted to be a crime in the case of an individual — is called a virtue when it is committed wholesale. Impunity is claimed for the wicked deeds, not because they are guiltless — but because the cruelty is perpetrated on a grand scale!

(c. 250, W), 5.277

Christians do not attack their assailants in return, for it is not lawful for the innocent to kill even the guilty.

(c. 250, W), 5.351

The hand must not be spotted with the sword and blood—not after the Eucharist is carried in it.

(c. 250, W), 5.488

Cyprian is especially valued in his writings for giving insights into the thoughts of underground Christians in the middle third century, and he concludes that the horrors of war refute its practice for Christians. He notes that the evils of war committed by one side are overlooked by people simply because people have widely agreed together to commit them. He rightly objects that such reasoning is unfit for the Christian mind. He also affirms that it was not permitted for Christians to even kill the guilty because those who observe the Lord’s cup must not be stained with the bloodshed of violence.

Lactantius

Lactantius (ca. 240–ca. 320), named Lucius Caelius Firmianus Lactantius, was invited to the Emperor Diocletian’s capital at Nicomedia to teach rhetoric. When he there, probably from North Africa, he was converted to Christianity and promptly lost his position. Eventually the Emperor Constantine chose him as tutor for his son Crispus, an act that brought him to Gaul about 313.

Lactantius wrote on war:

When the worship of God was taken away, men lost the knowledge of good and evil.… They then began to fight with one another, to plot, and to achieve glory for themselves from the shedding of human blood.

(c. 304–313, W), 7.141

If only God were worshiped, there would not be dissensions and wars. For men would know that they are the sons of one God.

(c. 304–313, W), 7.143

Why would [the just man] carry on war and mix himself with the passions of others when his mind is engaged in perpetual peace with men? Would he be delighted with foreign merchandise or with human blood—he who does not know how to seek gain? For the Christian is satisfied with his standard of living. He considers it unlawful not only to commit slaughter himself, but also to be present with those who do it.

(c. 304–313, W), 7.153

How can a man be just who hates, who despoils, who puts to death? Yet, those who strive to be serviceable to their country do all these things.… When they speak of the “duties” relating to warfare, their speech pertains neither to justice nor to true virtue.

(c. 304–313, W), 7.169

Therefore, it is not befitting that those who strive to keep to the path of justice should be companions and sharers in this public homicide. For when God forbids us to kill, He prohibits more than the open violence that is not even allowed by the public laws. He also warns us against doing those things that are considered lawful among men. For that reason, it will not be lawful for a just man to engage in warfare, since his warfare is justice itself. Nor is it lawful for him to accuse anyone of a capital charge. For it makes no difference whether you put a man to death by word, or by the sword instead. That is because it is the act of putting to death itself that is prohibited. Therefore, with regard to this commandment of God, there should be no exception at all. Rather, it is always unlawful to put a man to death, whom God willed to be a sacred creature.

(c. 304–313, W), 7.187

It is not right that a worshiper of God should be injured by a another worshiper of God.

(c. 304–313, W), 7.271

Lactantius continues the belief that Christians cannot engage in any violence by drawing on the world’s descent into violence after the fall in the days that culminated in the flood, when God destroyed the world because people filled it with their violence. Accordingly, violence is the evidence of those who have lost the knowledge and worship of God. Therefore, peace is the evidence of those who have received the knowledge of God and worship him in spirit and truth. He also concludes that no just man will engage in war on the grounds that such justice will universally lead such a person to peace. To engage in warfare would necessarily engage someone in conduct that would preclude them from being considered “just”.

Summary

The writings on war by early Christians are simply too numerous to include in full here, but what is most striking is that, to the extent that I have access to their writings, their agreement on this subject is actually universal: I found not a single dissenting voice in the first 300 years of Christian writings. My collection of writings after 300 years up to 600 years is not as extensive, but also yielded few exceptions to this interpretation other than those raised by under the influence of Emperor Constantine, who saw the Church as a useful tool for the State and subsequently changed the entire course of the universal Church for the worse.

Works Cited

War. (1998). In D. W. Bercot (Ed.), A Dictionary of Early Christian Beliefs: A Reference Guide to More than 700 Topics Discussed by the Early Church Fathers (pp. 676–681). Hendrickson Publishers.

Schaff, P., & Schaff, D. S. (1910). History of the Christian church (Vol. 2, p. 730). Charles Scribner’s Sons.

Hodge, C. (1997). Systematic theology (Vol. 1, p. 69). Logos Research Systems, Inc.

Elwell, W. A. (2001). In Evangelical dictionary of theology: Second Edition (p. 668). Baker Academic.