Attitudes to Holy War

What makes a war ‘holy’?

A holy war is a war fought for a religious cause, often believed by its supporters to be commanded or supported by God. Its defining feature is its religious justification, not simply that the people fighting belong to a religion. A war involving Jewish people is therefore not automatically a Jewish holy war.

This raises a difficult question: can fighting and killing ever fulfil a religious duty? Some Jews argue that obedience to God or the defence of endangered lives can make fighting necessary. Others emphasise that religion should lead people towards peace rather than give violence sacred approval.

Milchemet mitzvah: when fighting is a duty

Milchemet mitzvah means an obligatory or commanded war. In Jewish teaching, this includes wars understood as fulfilling a divine command and wars necessary for defence against attack. Unlike a merely permitted war, called milchemet reshut, it is understood as a duty rather than an optional choice.

The Torah contains accounts of divinely commanded conflict. For example, Exodus 17:16 describes the Lord’s war against Amalek. Such passages can support the belief that warfare is not always incompatible with serving God: in particular circumstances, fighting may be understood as obedience to God.

Defence also connects warfare with pikuach nefesh, the principle of saving human life. A Jew who accepts defensive war may reason that refusing to fight could leave innocent people exposed to death. From this perspective, preserving life can sometimes require force rather than complete non-resistance. However, this is not permission to fight for greed, power or hatred, nor does it make every claimed religious cause legitimate.

2 Samuel 22: David’s song of deliverance

In 2 Samuel 22, David sings to God after being delivered from his enemies and from Saul. The chapter is a song of thanksgiving: David attributes his rescue and success to God rather than to his own strength alone.

He calls God ‘my rock, and my fortress, and my deliverer’ in verse 2. A rock and fortress suggest security and protection. In verse 3, David says, ‘Thou savest me from violence.’ God is presented as a refuge for someone facing danger.

The song also contains strong military language. Verse 35 describes God as the one ‘Who traineth my hands for war’, while verse 40 declares, ‘Thou hast girded me with strength unto the battle’. David understands his ability to fight and overcome his enemies as coming from God. These verses can support the argument that God may help people in warfare and that fighting is not necessarily contrary to faith.

However, this is David’s account of deliverance, not a general command for every believer to wage war. The chapter also links God’s favour with righteousness and keeping God’s ways in verses 21–24. A claim to divine support therefore cannot simply replace questions about whether a cause and its conduct are right. Jews may differ over how far an ancient account of God helping David should guide decisions about warfare today.

Peace remains the ideal

Judaism strongly values shalom: peace understood as wholeness and harmony, not merely a temporary absence of fighting. Isaiah 2:4 describes people beating ‘their swords into ploughshares’. Turning weapons into farming tools represents a future in which resources sustain life rather than destroy it.

Deuteronomy 20:10 instructs those approaching a city to fight against it to offer peace. Many Jews draw from this the principle that peaceful solutions should be sought before warfare. Negotiation and diplomacy matter because they may protect lives without the suffering that war causes.

Tikkun olam, repairing the world, also encourages work towards peace and justice. For Jews who accept war in some circumstances, peace can remain the goal: fighting is a regrettable means of protecting people, not an ideal in itself. Permission to fight does not remove responsibility for how a war is conducted. Innocent people should be protected, and unnecessary harm to civilians and the environment avoided.

Why Jewish responses differ

Some Jews, including some Orthodox Jews, place particular weight on the authority of divine commands and the duty of defence. They may regard necessary defence of Israel as milchemet mitzvah. Their reasoning is that allowing an aggressor to kill people would fail to protect life. This does not mean that they approve every military action or every claim that a war is holy.

Other Jews give greater emphasis to peace, diplomacy and the dangers of using religion to justify violence. Reform and Liberal approaches may particularly emphasise these concerns, although support for defence and concern for peace cross denominational boundaries. A Jew can support necessary defensive action without describing a modern conflict as a holy war.

Some Jews are pacifists. They argue that war’s destruction of human life conflicts with the priority of peace. Those who disagree respond that refusing all warfare may allow violent aggressors to harm the very people Judaism requires believers to protect. The disagreement is therefore partly about how best to honour life, not simply whether life matters.

Atheist and Humanist objections—and Jewish responses

Atheists do not believe in God, so a supposed divine command cannot provide them with a convincing justification for warfare. Atheism alone does not determine whether someone supports defensive war or pacifism: an atheist may reject religious warfare but accept force for ethical or practical reasons.

Humanists base moral judgements on reason, empathy and human wellbeing. They generally reject holy war because religious authority is not sufficient evidence that violence is right. They favour peaceful solutions, although some accept defensive war to protect people and human rights. Others may take a pacifist position.

A central objection is that claiming God supports a war can discourage criticism: opponents may be treated as enemies of God rather than people whose lives also matter. Jews who prioritise peace can share this concern and agree that religious language must not excuse unnecessary violence. They can also cooperate with Humanists and atheists in peacebuilding despite having different foundations for their ethics.

A Jew who accepts milchemet mitzvah may respond that God’s authority is morally significant and that defence can be a religious duty. The disagreement then concerns both the existence of divine authority and whether a particular war genuinely fulfils that duty.

Reaching a justified judgement

A strong case for holy war is that, if God commands an action and defence is necessary to save lives, fighting may be a duty rather than a rejection of religious values. The strongest challenge is that a claim of divine approval is disputed and may be used to justify avoidable suffering.

One defensible conclusion is that necessary defence may be justified, but calling it ‘holy’ does not by itself establish that it is right. This recognises the protective role of force while requiring the cause and conduct of warfare to be judged against the priority of life and peace.