Pope Leo XIV Moving Towards Declaring that Illegitimate War is ‘Contrary to the Gospel’

I was in Rome, Italy, on March 29, 2026, when, at his very first Palm Sunday Mass, Pope Leo XIV dared to preach words that stunned the square and echoed across the Church: “Brothers and sisters, this is our God: Jesus, King of Peace, who rejects war, whom no one can use to justify war. He does not listen to the prayers of those who wage war, but rejects them, saying: ‘Even though you make many prayers, I will not listen: your hands are full of blood.’” I almost wish we had chosen to worship in Saint Peter’s Square that morning, so that with my own ears I could have heard what I knew Pope Leo XIV was eventually going to press forward in the advancing the Church’s teaching on life and human diginity, to insisit on a more rigorous discernment of legitimate defense and a clearer recognition, given modern weapons and their immense destructive power, including the way these can make it difficult to avoid evils and disorders graver than the evil to be eliminated, and given how easily parties can pursue ‘partisan interests’ (e.g., the military‑industrial complex) rather than the universal common good, that it is often very difficult to satisfy the just-war criteria in practice.

Despite the ensuing criticism from political and Catholic commentators, Pope Leo XIV’s core move—using Isaiah 1:15 to argue that prayer cannot be reconciled with bloodshed and warfare justified by religious language – fits comfortably within the Catholic tradition. Origen, St. Clement of Alexandria, St. Cyprian of Carthage, St. John Chrysostom, St.  Thomas Aquinas, and St. John Paul II all used this verse to teach that God’s “not listening” signifies a refusal of complicity with bloodshed. Even in his 2023 Vespers homily for the Solemnity of the Conversion of Saint Paul, Pope Francis explicitly cited Isaiah 1:13, 15, and 16, applying them to “sacrilegious violence” and to the scandal of Christians committing or tolerating brutality, especially wars and acts of violence. In that sense, there was nothing new in what Pope Leo XIV taught about the incompatibility of prayer with bloodshed and war when justified by religious rhetoric.

What was new or distinctive in Pope Leo XIV’s Palm Sunday homily was not the underlying logic—Isaiah’s warning that God does not accept religious devotion when violence and injustice remain unrepentant is a constant across the Fathers and modern papal teaching—but rather the rhetorical packaging he chose: “Jesus, King of Peace, who rejects war…” Traditionally, the Church has read Isaiah’s rebuke as a moral‑spiritual indictment: God rejects worship and sacrifice when they are divorced from justice and a purified heart, while “the prayers of the upright are acceptable” because righteousness is more pleasing than offering. Pope Leo XIV, by contrast, draws on that same principle but presents it with a more explicitly Christ‑centered and contemporarily applied focus—linking Isaiah’s “not listening” to Christ’s identity as King of Peace and to the practical impossibility of invoking God as a warrant for bloodshed while simultaneously praying. (Cf. Clement of Alexandria, Stromata, Book 7, Chapter 18.)

Development of doctrine, our confidence that the Spirit will guide the Church “into all truth” (Jn 16:13), never happens in an instant, as though someone simply flipped a switch. But if we pay careful attention, we can discern the direction in which the Spirit is leading the Church. For example, it was already clear that the Church would eventually move away from her earlier tolerance of state‑sanctioned killing when Gaudium et Spes decisively rejected the long‑standing acceptance of torture, teaching: “Whatever violates the integrity of the human person, such as mutilation, physical and mental torture, and attempts to coerce the will itself… are infamies indeed” (GS 27). That moment signaled a deeper moral trajectory, one that would later mature in Veritatis Splendor and culminate in the Church’s definitive judgment that the death penalty is now “inadmissible.”

Indeed, to the average person today, it may seem strange that the Catholic Church ever permitted torture at all. Since we live in a society that has largely removed torture from the administration of capital punishment, preferring the notion of a “humane” execution, the older teaching can feel alien. But for most of human history, torture was not an aberration; it was either the means by which the death penalty was carried out or its grim prelude. From 1252 onward, with Ad extirpanda (“…the podestà and rulers of the cities shall force all heretics… to confess their errors; and they may use torture, but without danger to life or limb”), the Church tolerated its use. Yet once Gaudium et Spes effectively rendered the logic of Ad extirpanda obsolete by condemning torture as an ‘infamy’, it became clear that the Spirit was leading the Church toward a deeper recognition of the inviolable dignity of the human person.

Once Veritatis Splendor re-grounded the Church’s moral theology in the person of Christ Himself, rather than in proportionalist or consequentialist calculations, it became possible to see how Gaudium et Spes had already cast a bright light on the emerging consensus within episcopal conferences around the world. The Holy Spirit’s guidance becomes visible when you trace those early signals. For example, the Indian Bishops’ Conference in 1969 called for the abolition of the death penalty on the grounds that modern society possessed “other effective means” to protect the common good. Likewise, in the United States, the USCCB’s 1974 statement urged a “presumption against capital punishment,” anticipating the deeper doctrinal developments that would follow. These early episcopal judgments were not isolated opinions; they were the first fruits of a moral trajectory that Veritatis Splendor would later anchor explicitly in Christ’s own revelation of the human person.

It would be fifty‑two years later, in 2017, when Pope Francis inserted into the Acta Apostolicae Sedis—the official record of the Apostolic See—the authoritative judgment that the death penalty is “contrary to the Gospel.” That phrase is not an innovation ex nihilo; it is the direct continuation of the Christocentric moral vision articulated in Veritatis Splendor. If the Church’s moral theology must reflect the morality of Christ Himself, then it must reflect the One who, at every turn, chose life. Even when the world gave Him death, He responded by giving His people life, and by preparing for them a path of life through the life‑giving and life‑affirming sacraments and liturgy. The Church’s rejection of the death penalty, therefore, is not a departure from her tradition but the maturation of it—an ever‑clearer conformity to the Lord who conquered death not by wielding it, but by overcoming it.

Now returning to Pope Leo’s statement that seems to strike at the heart of most wars are contrary to the Gospel, we can see that his Palm Sunday homily does not stand alone. It sits within a half‑century of magisterial tightening around the morality of war, a pattern remarkably similar to the Church’s development on the death penalty. The shift begins already in Gaudium et Spes, which famously declared that “the horror and perversity of war is immensely magnified” in the modern age and that acts of war aimed at indiscriminate destruction are “a crime against God and man” (GS 80). John Paul II deepened this trajectory by repeatedly insisting that modern warfare rarely meets the classical just war criteria, calling the Gulf War and later conflicts “a defeat for humanity” and warning that contemporary weapons make true discrimination between combatants and civilians nearly impossible. Benedict XVI continued this line, teaching that peace is not merely the absence of war but the fruit of justice and integral human development, a moral horizon that renders war increasingly incompatible with the dignity of the human person. The Compendium of the Social Doctrine of the Church (2004) stated that modern warfare “poses an enormous threat to humanity” and that the just‑war criteria must be interpreted “with great strictness.”

By the time we reach Pope Francis, the pattern becomes unmistakable. In Fratelli Tutti, he states plainly that “we can no longer think of war as a solution” and that the just‑war tradition “can be interpreted too broadly,” leading to moral distortion rather than moral restraint (FT 258). He goes further, arguing that with today’s weapons and geopolitical realities, “it is very difficult nowadays to invoke the rational criteria elaborated in earlier centuries to speak of the possibility of a ‘just war’” (FT 260). This is precisely the kind of pre‑magisterial groundwork that preceded the Church’s eventual judgment that the death penalty is “inadmissible.” Pope Leo XIV’s Palm Sunday teaching, that Christ the King of Peace “rejects war” and does not hear the prayers of those who wage it, is best understood as the next step in this same Spirit‑guided maturation. Just as the Church came to see that the death penalty contradicts the Gospel, she is now discerning that modern warfare, in its methods and effects and corporate interests, stands in similar contradiction to the peace revealed in Christ.