Can Nations Justify War by Citing the Hebrew Bible?

The Old Testament is full of bloody wars, but Christ gave us a new commandment: "to love one another". Hence, the Church developed just war theory.

From Aleteia

By Philip Kosloski & Daniel Esparza

The argument sounds biblical, but it fails both theologically and politically.

When modern states invoke the Hebrew Bible to defend war, they usually make a simple move: ancient Israel fought enemies in the name of God, so nations today may do the same. The argument sounds biblical, but it fails both theologically and politically.

The first problem is historical. Ancient Israel was not unique simply because religion and politics were intertwined. That was the normal structure of the ancient world. Egyptian pharaohs ruled as divine figures; Mesopotamian kings claimed patronage from gods such as Marduk or Ashur; rulers across the region attributed military victories to heavenly favor. In that sense, Israel was not unusual.

What makes Israel distinctive in Scripture is something else entirely: its place in a specific covenantal narrative. The Hebrew Bible presents Israel not simply as another nation invoking divine support, but as a people bound to God through covenants with figures such as Abraham and Moses. Those covenants were not primarily geopolitical arrangements. They were part of a larger drama in which God forms a people through whom the knowledge of the one God — and ultimately salvation — would enter the world.

Within that story, certain conflicts appear as episodes in that unfolding history. They are tied to particular promises, prophetic guidance, and judgments described within the narrative itself. Because they belong to that unique covenantal framework, they cannot be detached from it and turned into a standing principle for every later nation. The biblical text is describing events within salvation history, not laying out a permanent blueprint for religious warfare.

Revelation in Christ

Catholic theology makes that limit even clearer by insisting that revelation reaches its fullness in Christ. Dei Verbum teaches that God’s self-disclosure culminates in the Son, and the Catechism states that “no new public revelation is to be expected” before Christ’s return.

A government, then, cannot simply place itself in Israel’s biblical role and announce that God has commissioned its campaign. The Church does not recognize modern states as recipients of fresh public revelation that would authorize conquest in God’s name.

There is also a moral-development point. The Catechism explains that the Old Law functioned as a preparation for the Gospel, while the Law of the Gospel fulfills and surpasses it. For Christians, the Hebrew Bible must therefore be read through the teaching of Christ. Scripture cannot be treated as a collection of reusable precedents for political violence. The trajectory of revelation moves toward mercy, reconciliation, and the transformation of the human heart.

Political theory reinforces the same conclusion. A modern state is not identical to a biblical covenant people. Its authority is public, legal, and limited; it governs through institutions, not prophetic certitude. Even where leaders use religious language, they remain political actors whose decisions must be evaluated through moral reasoning.

In the classical Christian tradition, that evaluation takes the form of just war reasoning, not appeals to “holy war.” The Catechism permits military force only under strict conditions: grave and certain harm, legitimate authority, proportional means, a serious chance of success, and the exhaustion of peaceful alternatives. Even then, war is understood as a tragic necessity rather than a sacred mission. The same teaching insists that governments and citizens are obliged to work constantly for the avoidance of war.

That is the Catholic answer. Nations cannot justify war by citing Israel’s battles in the Hebrew Bible as though those texts were timeless licenses for sanctified violence. Those passages belong to a specific covenantal history interpreted in light of Christ. Modern states must answer instead to moral law, prudential judgment, and the demanding discipline of just war teaching.