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Markkula Center for Applied Ethics

Ethics and War in Comparative Religious

Dr. David Perry

Presented at Los Gatos Unitarian Fellowship, 2 April 2000

War is a peculiar human activity, in that it can bring out some of our best traits, such as courage and self-sacrifice, yet also elicit tremendous cruelty and suffering. It’s therefore a prime candidate for ethical reflection. Although each of the world’s major faith traditions preaches compassion and justice, many of the most horrendous wars in human history have ironically been fought in the name of religion. Even now, at the beginning of the 21st century, people are still strongly divided by religion. Religion continues to be a catalyst for war in places as diverse as Yugoslavia, Nigeria, Ireland and Indonesia. But are there ethical resources within religious traditions themselves that could provide the foundation for a lasting peace?

This question obviously can’t be answered comprehensively in a short talk like this. But allow me to sketch the following argument: 1) Each of the major religious traditions contains moral rules or principles bearing on war that contradict one another to some extent. 2) Believers within those traditions cannot act in accordance with contradictory moral rules, since that would entail performing an action and not performing it at the same time, which is impossible. 3) Therefore, believers must choose to reject at least some of their own traditional rules. 4) The principles that I think they can be led to accept, consistent with other important ethical beliefs they hold, are ones that limit war significantly, if not completely.

My comments will focus primarily on Christianity, but I’ll also make some comparative points about Judaism, Islam, and the religions that originated in India. I’ll start with those with which I’m least familiar.

The Hindu tradition contains a very strong ethic of reverence for life. To kill or harm another creature is a serious offense that corrupts one’s soul and delays one’s achievement of enlightenment. But Hindu ethics have also been strongly influenced by the caste system with its fatalism and narrow role expectations. One of the main castes is that of the warrior. If a person is born into the warrior caste, he is obliged to kill enemy soldiers if needed to defend the religious community. On the other hand, total war in the sense of indiscriminate killing seems to have been prohibited fairly consistently. Hindu soldiers are not to kill prisoners, the wounded, deserters, or noncombatants. Why not? Apparently out of a sense of fairness or chivalry: it would be "unprofessional" to attack non-soldiers (Klostermaier 230).

Jains and Buddhists, who generally reject the caste system and consider the ethic of nonviolence to be binding on all people (Ferguson chs. 3-4), nonetheless do not completely prohibit the taking of life. They avoid killing sentient animals, but they accept the killing of plant life even though they consider plants to have souls. More to the point, some Buddhists also think it can be right to kill an unjust human attacker if necessary to save the lives of two or more innocent people (Ferguson 55-56).

Turning now to the Jewish tradition, one of the Ten Commandments listed in Exodus 20 is "Thou shalt not kill." Was that meant to be an absolute prohibition of all killing? Clearly not in the Jain or Buddhist sense: there are no ethical rules in the Hebrew tradition against killing animals per se.

We might think that the Hebrew Commandment applies to all killing of people, especially if we consider the idea expressed in Genesis 1 that human beings are created in God’s image or likeness. That would seem to imply that they have infinite dignity and value, and should never be killed. But apparently the Hebrew Bible did not intend to prohibit killing people completely: the proper translation of the Exodus passage is "Do not commit murder," which presumably covers some killing but not all. Also, in Exodus chs. 21-22 and elsewhere, God is said to command killing--in the form of capital punishment--for many offenses including murder, kidnapping, and striking or cursing one’s parents.

But given that murder is prohibited, we might assume that the ancient Hebrews would have considered total war to be morally unacceptable. But that was not the case. The first of the Commandments prohibited the Israelites from worshipping any other gods but Yahweh. God demanded purity and strict obedience. Idolatry and blasphemy were punishable by death. Non-Israelites who lived within the area believed by the Hebrews to have been promised to them by God were seen to pose a great temptation to them to abandon their faith. This led them to justify the slaughter of entire cities and "everything that breathed" in them (Bainton 48-49). (See Joshua 6 and 10 and Deut. 7. Whether such massacres actually occurred is irrelevant here.)

It’s somewhat surprising that a slightly different set of rules was prescribed (in Deuteronomy 20) for dealing with Israel’s external enemies (Bainton 43). An ultimatum was given to them to submit to forced labor, or all men would be killed and the rest enslaved. That’s not much of a choice, but somewhat different from killing "everything that breathed." Unfortunately for us in trying to interpret this text, no reasons are given to explain this difference. Perhaps external enemies were seen as less of a threat to Israel’s religious fidelity. (But foreigners would be considered idolaters, too….)

In the Islamic tradition there are also precedents for total war. Although Muhammad was said by an early biographer to have taken the path of non-violence at first, he soon came to justify the use of force not only in defense of his growing religious community but also in the form of offensive war to expand the territory of Islam. And the rules he set for fighting such wars were fairly harsh: although women, children and the elderly were not to be directly attacked, Muhammad permitted his warriors to kill all captured soldiers and male civilians. Also, when foreign women and children were killed by Muslim soldiers in battle, Muhammad denied that they were responsible, placing blame on the enemy leaders instead. This is a claim which unfortunately continues to be made today by leaders of Islamic terrorist groups, who accept no moral guilt for killing innocent civilians (Kelsay 21-22, 59-60, 63, 104).

On the other hand, there are other ethical ideas within the Hebrew and Islamic traditions that tend to rule out total war. Both traditions believe God to be compassionate and merciful, and urge people to imitate God in those respects. They also prescribe punishments in some cases only for those who are guilty of offenses, which would prohibit the use of force against innocent noncombatants. And there are many Jewish and Muslim authorities today who argue that war should only be waged as a last resort, and that only the minimum degree of force necessary should be used. For example, the "Ethical Code of the Israeli Defense Forces," which incorporates many Jewish ethical values, requires soldiers to "prevent unnecessary harm to human life and limb, dignity and property … with special consideration for the defenseless." There are also influential Muslim leaders today who completely condemn terrorism against innocent civilians, and limit the recourse to war to defense alone (Kelsay 105-106, 109-110).

In the Christian tradition, one finds the full range of ethical views on war, from pacifism to limited war to total war. Historically, that’s roughly the order in which those views developed (Bainton 14).

Jesus set very high standards for his followers on love and forgiveness, including non-retaliation against evil and love of enemies: "You have heard it said, 'An eye for an eye, a tooth for a tooth.' But I say to you, do not resist those who wrong you. If anyone slaps you on the right cheek, turn and offer him the other also…. You have heard it said, 'Love your neighbor and hate your enemy.' But I tell you, love your enemies and pray for your persecutors." (Matthew 5:38-39, 43-44; compare Luke 6:27-29.) Most early Christians seem to have interpreted Jesus's order to prohibit all uses of force, even in defense of the innocent.

According to Matthew 26, when a mob of armed men came to arrest Jesus, one of his disciples (assumed to be Peter) "drew his sword, and struck the slave of the high priest, and cut off his ear. Then Jesus said to him, 'Put your sword back into its place; for all who take the sword will perish by the sword.'" Many early Christians also noted that Jesus allowed himself to be unjustly executed without putting up any resistance. Paul echoed Jesus's nonviolent message in his letter to the Romans, ch. 12: "Repay no one evil for evil ... never avenge yourselves, but leave it to the wrath of God.…"

On the other hand, some New Testament passages were interpreted by later Christians as affirming the military profession and its use by the state. Roman soldiers who met Jesus, John the Baptist, Peter and Paul were apparently not asked by any of them to abandon their roles. And in Romans 13, Paul wrote: "Let every person be subject to the governing authorities. For there is no authority except from God, and those that exist have been instituted by God." He who is in authority "is the servant of God to execute his wrath on the wrongdoer." Paul seems to permit the state to use force, but not individual Christians.

Many other Christians in the first three centuries after Christ advocated pacifism (Swift 34-60). Justin Martyr urged Christians not to take part in wars but to pray for their enemies and not resist those who imprison or kill them because of their faith. Athenagoras said that Christians must allow themselves to be hit and robbed without retaliating either physically or through the courts. Tertullian thought that holding public office and being a soldier would inevitably require actions forbidden to Christians, and connected personal non-retaliation with abstaining from government and military service. "Will a son of peace who should not even go to court take part in battle?" he asked rhetorically. For Christians "it is more permissible to be killed than to kill." And in disarming Peter, Jesus "disarmed every soldier thereafter." Hippolytus thought that Christians should not join the army; but if they were already in the army, they must disobey orders to kill. That of course would not have gone over well with their military superiors, and might have resulted in their execution. Origen was aware of Old Testament holy wars, but said that "the Christian Lawgiver [i.e., Jesus] made homicide absolutely forbidden." "The law of gentleness and love" precluded vengeance and violence.

Although the pacifist stance is strong during this early period, there are also hints of some permissible uses of military force. Curiously, considering their otherwise strongly pacifist stances, Tertullian prayed for imperial Rome and its "brave armies," and Origen prayed on behalf of soldiers "doing battle in a just cause and on behalf of an emperor who is ruling justly." (Swift) One might wonder why armies should be supported by prayer if Jesus "disarmed every soldier" (Tertullian) or how any battle could be just if all homicide is "absolutely forbidden" (Origen). Their stance may be consistent with that of Paul, though, i.e., prohibiting violence by individual Christians but seeing God's purposes in some uses of force by governing authorities.

Although some Christians served as Roman soldiers during the Church’s early history, a very significant shift in Christian thinking about war occurred in the fourth century when Emperor Constantine began to use the Roman state to support the Church. According to an influential bishop named Eusebius, Christian pacifism was from then on to be strictly for clergy, monks and nuns; lay Christians, by contrast, were obligated to defend the empire with force (Swift 82-89).

Ambrose, Bishop of Milan, believed that Christians may not use force in personal self-defense, apparently in light of Jesus' commands in the Gospels not to resist or retaliate against evil. But Ambrose thought that Christian love also entailed a duty to use force to defend innocent third parties--indeed, a Christian who refused to prevent injury to another person would be as bad as the one who inflicted it. Ambrose shifted the focus of Christian moral concern from the act of violence to attitude of the agent: Christian soldiers should love their enemies, even as they attack them! (Is that possible psychologically?) In effect, he "baptized" Roman military virtues for Christian purposes: risking one's life to defend the empire became courageous, just and noble for Christians. Ambrose believed that there should be moral limits on war, however. (Swift 96-110)

With Ambrose and his student Augustine appears the first significant Christian development of just-war principles. They stipulated that war must only be waged by a legitimate governmental authority; it must be intended to restore peace and justice; it must be avoided altogether if justice can be achieved by nonviolent means, i.e., war should only be used as a last resort. There were also limits on the conduct of war: reprisal killings and massacres were forbidden (Bainton 95ff.).

Even in cases where Augustine considered war to be the lesser of evils, he regarded killing as ultimately tragic, always requiring an attitude of mourning and regret on the part of Christians. Partly due to his influence, throughout most of the medieval period, killing in war was considered a very serious sin. If a Christian soldier killed an enemy soldier, even in a war that was considered just overall, that soldier would have to do penance for the killing, usually by fasting and prayer for a year or more (Bainton 98, 109).

But later efforts by medieval popes to reduce conflict among European princes ironically led to larger wars against external enemies: the Crusades. In the year 1095, Pope Urban II urged European leaders to stop quarrelling among themselves, and to rescue the Christian holy lands from their non-Christian occupiers. He referred to the Turkish Muslims who had invaded Palestine as a "cursed race" and an "unclean nation" that had polluted Christian holy places. Killing Muslims became itself a form of penance for Christians for remission of their sins. Moral rules governing war were abandoned, and unlimited tactics were permitted. No one was immune from attack by Christian crusaders; whole cities were slaughtered. (Bainton 109-112)

There seems to be a tendency in human societies to believe that one's own enemies are the enemies of God, and need not be treated with the same sort of respect that one is required to show to one’s fellow citizens. In some cases people are led to believe that the impurity or evil of their enemies is so deep that they ought to be exterminated. There are still people today who believe that their faith has a monopoly on the truth. And many of them are quite willing to use force, even total war, to spread their faith at the expense of others.

What the advocates of aggressive religious war cannot legitimately claim, though, is that their position is the only authentic expression of their faith. Every major religious tradition contains ethical principles that are incompatible with total war. Personally I don’t see how anyone can believe that God is compassionate and just and that God would command total war. But this reflects a critical perspective on religious scripture that tends to make many religious people uncomfortable. It’s not easy to convince them that they can analyze their scriptures critically, perhaps even coming to reject some ideas contained in them, without necessarily blaspheming God or abandoning their faith. But I think it’s imperative for people to come to grips with contradictory ideas that exist even in their most sacred books.

I’m encouraged by the fact that leaders of the major religious traditions have engaged in sincere interfaith dialogues, in part to reduce the ignorance, fear and hatred that often leads to war, but also to seek areas of agreement on ethical matters even if they cannot agree theologically. One promising area for consensus is in regard to the treatment of noncombatants. People of all faiths can agree, I trust, that innocent civilians should never be directly targeted by military forces, that indiscriminate weapons and tactics should never be used against military targets in ways that would produce large civilian casualties, and that captured soldiers should not be tortured or executed but treated humanely.

If a belief that God is compassionate and just is incompatible with advocacy of total war, is it also incompatible with war of any kind? Should religious people be strict pacifists?

I don’t think so. I can understand why people might see nonviolence as the logical extension of compassion. It seems impossible to reconcile love of enemies with killing them, as Ambrose and Augustine tried to do. But I think (with A & A) that an absolute refusal to kill is inconsistent with compassion and justice for innocent people threatened with violent attack. Consider, for example, the continuing need to use military force to stop "ethnic cleansing" and genocide. I also think (against A & A) that people have a right to defend themselves, not only an obligation to defend others. An unjust, violent attacker in effect forfeits his right not to be killed by others.

On the other hand, it’s a very grave thing to kill any person. Given the potential for mass killing that’s inherent in all modern war, we must take on the burden of wrestling with the ethical criteria that war must satisfy if it is ever to be permitted.


Roland Bainton, Christian Attitudes toward War and Peace, 1960.

"Ethical Code of the Israeli Defense Forces," on the web at

John Ferguson, War and Peace in the World’s Religions, 1978.

John Kelsay, Islam and War: A Study in Comparative Ethics, 1993.

Klaus Klostermaier, "Himsa and Ahimsa Traditions in Hinduism," in Harvey Dyck, ed., The Pacifist Impulse in Historical Perspective, 1996.

M. Jack Suggs et al., eds., Oxford Study Bible, 1992

Louis Swift, The Early Fathers on War and Military Service, 1983.

Also Recommended:

Anthony Coates, The Ethics of War, 1997.

David Perry is the Director of Ethics Programs, Markkula Center for Applied Ethics, and Lecturer in Religious Studies.

Apr 2, 2000
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