Many have noted that a central theme of the papacy of Pope Leo XIV is peace.[1] In his 9 January 2026 address to the members of the diplomatic corps accredited to the Holy See, the pope underlined its nature and urgency.[2] Therein, Pope Leo made a crucial clarification between true and false visions of peace, one finally rooted in Christ, and finding a theoretical elaboration in the “Two Cities” doctrine so dear to Saint Augustine. The difference between these two understandings of peace has profound implications for the human social order, not least with respect to two other key terms: truth and justice. Ultimately, the orders of peace, truth and justice are complementary and grounded in the fullest reality of right relations between God, the human person, and all of creation. A distortion of any one of those three, whether in the theoretical or practical order, runs the risk of serious dangers for the whole human family.
A right understanding of peace is thus of the utmost importance to the diplomacy of the Holy See. Even with their eyes fixed on Christ, Pope Leo told the diplomats, “Christians living in the earthly city are not strangers to the political world, and, guided by the Scriptures, seek to apply Christian ethics to civil government.”[3]
What is Peace?
It is a commonplace to refer to a false notion of peace based upon an absence of conflict, as with the famous line of the Roman historian Tacitus: “They make a desert and call it peace.”[4] Pope Leo has noted in other places, for instance, that “All too often we consider [peace] a ‘negative’ word, indicative only of the absence of war and conflict, since opposition is a perennial part of human nature, frequently leading us to live in a constant ‘state of conflict’ at home, at work and in society.”[5]
The pope’s formulation invites further questions about the true nature of peace. Why is peace so elusive? And why is conflict so endemic to human life: “a perennial part of human nature”? Pope Leo takes up such questions in his January 9, 2026, address by turning to Saint Augustine. As the pontiff has reminded us, the great African Doctor of the Church offers a narrative history of sin and salvation of enduring value through his “Two Cities”: “First, there is the city of God, which is eternal and characterized by God’s unconditional love (amor Dei), as well as love for one’s neighbor, especially the poor. Then there is the earthly city, which is a temporary dwelling place where human beings live until death. In our day, the latter includes all social and political institutions, from the family to the Nation State and international organizations. For Augustine, this city was epitomized by the Roman Empire. Indeed, the earthly city is centered on pride and self-love (amor sui), on the thirst for worldly power and glory that leads to destruction.”[6]
In calling this doctrine to mind, Pope Leo reminded the diplomatic corps that this distinction is not only external and visible, but also invisible and mysterious: it concerns the orientation of the person toward God. This is why for Saint Augustine the two cities are created by two distinct orders of love.
This doctrine also names why conflict is indeed so endemic to the human condition and why peace is so rare: it is rooted in our primordial turn toward self and away from God. This turn does not remove them from the possibility of God’s grace, nor does it keep Christ’s mission from working through the Church. But it does mean that Christians are caught between the two cities, a condition finally resolved only by the Parousia. As Leo XIV says, “However, this is not a reading of history that seeks to contrast eternity with the present, the Church with the State, nor is it a dialectic about the role of religion within civil society.” For this reason, the pope told the assembled diplomats, “Christians are called by God to dwell in the earthly city with their hearts and minds turned toward the heavenly city, their true homeland.”[7]
Thus far, this is much in keeping with how many would present the Two Cities. The pontiff goes on to offer, however, a reflection on the connection between these two cities and two different visions of peace. For the pope, the two cities with their two loves correspond to two kinds of peace: there is the peace ultimately found in Christ, and there is the peace falsely sought in oneself, and one’s ability to remake the world in one’s own image.
Continuing with Saint Augustine, Leo XIV notes that everyone wants peace, “For even those who make war desire nothing but victory; they desire, that is to say, to attain to peace with glory.” But they do not thereby seek true peace, “but only the peace that they desire.”[8] This is the challenge for the earthly city: it cannot but seek peace, a peace however that is self-defeating, for it always leads to further violence in the name of self-love.
True peace, the pope has written in many places, comes to us as a gift of God. As he said in his Message on the LIX World Day of Peace, “‘Peace be with you’ (John 20:19, 21) is his Word that does not merely desire peace, but truly brings about a lasting transformation in those who receive it, and consequently in all of reality.[9]” “Peace exists,” the pope wrote in that Message, and “it wants to dwell within us.” Thus peace is finally the gift of God, the relationship within us that begins within each person and spreads through the world. Thus it is both “a presence and a journey”: something that gives us life here in the present, but also draws us beyond to better common life with others.
‘A difficult yet realistic good’
Peace is truly possible, but it is also difficult. Thus Christians face two temptations in the social order: to deny the practical possibility of peace because of its difficulty, or to promote it under a false account of its ease.
The temptation to deny the possibility of true peace is pervasive because of sin. The logic of violence is routinely valued over the logic of peace, Pope Leo argues, because pride is chosen over humility: “Yet, as Augustine notes, ‘great is the folly of pride in those individuals who think that the supreme good can be found in this life, and that they can become happy by their own resources.’ Pride obscures both reality itself and our empathy toward others. It is no coincidence that pride is always at the root of every conflict.”[10]
This pride can lead to a self-perpetuating loop, whereby “we lose our sense of realism and surrender to a partial and distorted view of the world, disfigured by darkness and fear. Many today call ‘realistic’ those narratives devoid of hope, blind to the beauty of others and forgetful of God’s grace, which is always at work in human hearts, even though wounded by sin.”[11]
This dynamic is not unique to our time, although in its more theoretically sophisticated guises it can take a specifically modern form of denying the transcendent: “While Saint Augustine highlights the coexistence of the heavenly and earthly cities until the end of time, our era seems somewhat inclined to deny the city of God its ‘right of citizenship.’ It seems that only the earthly city exists, enclosed exclusively within its borders. Seeking only immanent goods undermines that ‘tranquility of order,’ which, for Augustine, constitutes the very essence of peace, which concerns society and nations as much as the human soul itself, and is essential for any civil coexistence. In the absence of a transcendent and objective foundation, only self-love prevails, to the point of indifference to God governing the earthly city.”[12]
Here one cannot but think of the great political thinkers who have done so much to legitimize evil and conflict in politics, so as to render the very idea of peace utopian. Niccolò Machiavelli, for instance, was far from the first person to recognize the presence of evil in the world, much less the tragic necessity of making difficult choices in political life. His contribution, if it can be called that, rather “consists in having accepted, recognized, endorsed as a rule the fact of political immortality, and in having stated that good politics, politics conformable to its true nature and to its genuine aims, is by essence non-moral politics,” in the incisive commentary of Jacques Maritain, the French philosopher and friend of St. Paul VI. Machiavelli thereby, Maritain continues, places a “radical pessimism” at the heart of political life, and “consequently an illusory but deadly antinomy between what they call idealism (wrongly confused with ethics) and what they call realism (wrongly confused with politics).”[13]
It is in light of this background, a centuries-long rejection of peace, that leads the pontiff to offer an account of hope, a story about why peace is both possible and difficult. Again, any resistance to violence and force in the world has to be serious about the sources of that violence and conflict. Accounts of conflicts rooted in miscommunication or material scarcity are inadequate as a full theory about the violence and opposition in the world. The existence of the two cities is an eschatological reminder that conflict in the world begins with a conflict in human hearts and souls. This means that the conflict will have to be addressed at its most basic level, but also it will not be fully undone by merely human means. The tendency toward violence and conflict renders politics difficult, which is to say it renders entering into true politics difficult. But once one does, then the real difficulty begins: “While war is content with destruction, peace requires continuous and patient efforts of construction as well as constant vigilance.”[14]
In surveying the pope’s teaching on Saint Augustine, it is instructive to note that he avoids two extremes. The “Two Cities” doctrine, just because of its versatility, has been interpreted in manifold ways and adapted to a wide variety of political programs, from Jansenist to Whig. At one end, the Two Cities can be read as a counsel of despair: the earthly city is a spiritual wasteland which Christians should always and everywhere avoid, as though they were not called upon to seek the good of their neighbor. At the other extreme, the two cities can be collapsed together, as though Augustine calls upon Christians to conflate material progress with spiritual perfection. Neither of these is an accurate reading of Saint Augustine because neither of these is an accurate reading of reality, of which he was a keen student. Christians live their vocations in the public sphere bearing witness to two truths: 1) humans are called to cooperate with God in their salvation, and 2) such salvation remains a gift that ultimately only God can give.
The Family
The family has a special role in the pope’s address. In line with ancient tradition, Pope Leo understands the term “family” analogously, including the human family and the domestic family of man, woman and child. The latter has the focal meaning of the term. Any plan to build up the human family must take seriously the place where “we learn to love and foster the capacity to serve life, thus contributing to the development of society and the Church’s mission.”[15]
In underlining threats to the family like abortion and surrogacy, the pope recalls that “in its international relations and actions, the Holy See consistently takes a stand in defense of the inalienable dignity of every person.” Such threats not only directly harm the dignity of the persons thus subjected to them, but more broadly the foundations of that dignity in the family, in which the vocation of the person created imago Dei “is revealed in a privileged and unique way.”[16]
It is thus distressing, and the source of many problems, that families suffer from without, with the “worrying tendency in the international system to neglect and underestimate its fundamental social role, leading to its progressive institutional marginalization,” and from within, given “the growing and painful reality of fragile, broken and suffering families, afflicted by internal difficulties and disturbing phenomena, including domestic violence.”[17]
Here Pope Leo reminds the world in his characteristically clear but gentle way that marriage and family life rests upon “the exclusive and indissoluble union between a woman and a man.”[18] Pope Leo also made this point in his address to the Diplomatic Corps on May 16, 2025, with reference to his namesake’s encyclical Rerum Novarum, when he urged leaders “to build harmonious and peaceful civil societies” by “investing in the family, founded upon the stable union between a man and a woman, ‘a small but genuine society, and prior to all civil society’.”[19]
Pope Leo thus deepens our appreciation of the legacy of Leo XIII, which, extending beyond any one particular issue, rather lays out the foundations of modern Catholic social teaching. And the family is indeed vital to its foundations and its vision of peace.
Rights: Peace, Truth and Justice
Pope Leo’s analysis of human rights illuminates the interconnected dynamics between peace, truth and justice. The Church came to support the articulation of those human goods sought through public life in terms of modern subject rights – “human rights” – after the Second World War, not least because their advocacy found “institutional expression” in a host of international organizations developed after the war. Eighty years later, the family of nations is challenged to continue to seek those goods through responsible articulation and protection of human rights, which in turn require careful governance by the United Nations and other international agencies.
For Pope Leo, two kinds of rights are primary: the right to life, and religious freedom. They are crucial because of their reference to human nature: the former protects the sanctity of life, and the latter “expresses the most fundamental reality of the person.” Without them, other rights not only lose their foundations, but society risks inventing “self-referential” rights that are “disconnected from reality, nature and truth.”[20] Such counterfeit rights cut against the truth about who humans are, and thus do not serve to advance their goods or to promote justice. Indeed, they threaten our grasp of reality. Humans today face not only the challenge of “fake news,” in which what they read cannot be trusted, but language itself comes under attack by opportunistic ideologies, developing “a new Orwellian-style language” deployed as “a weapon with which to deceive, or to strike and offend opponents.”[21]
Faced with such chaos, Pope Leo sees “an actual ‘short circuit’ of human rights” whereby basic rights “are being restricted in the name of other so-called new rights, with the result that the very framework of human rights is losing its vitality and creating space for force and oppression.”[22] Thus part of a “healthy multilateralism,” called for repeatedly by Pope Francis and Pope Leo, includes the ability of governments and international organizations to recognize basic truths about humanity.[23] Beyond questions of institutional capacity and willpower, however important they may be, multilateral relations cannot be conducted fruitfully on the basis of false conceptions of humanity.
Not for the first time, the pontiffs return us to the anthropological question at the center of politics. As Pope Leo said to the diplomats, “Efforts are therefore needed to ensure that the United Nations not only reflects the situation of today’s world rather than that of the post-war period, but that it is also more focused and efficient in pursuing policies aimed at the unity of the human family instead of ideologies.”[24]
Pope Leo thus underlines a key presupposition of Catholic Social teaching, one fundamental to Leo XIII and particularly underlined by Benedict XVI in Caritas in Veritate and elsewhere: “the close connection between the truth of justice and the virtue of charity.” As the pope told the Roman Rota in January 2026 at the opening of the judicial year, “These are not two opposing principles, nor are they values to be balanced according to purely pragmatic criteria, but two intrinsically united dimensions that find their deepest harmony in the very mystery of God, who is Love and Truth.”[25] This is the deepest meaning of salus animarum, he told them: “that true love for neighbor that seeks above all else his eternal salvation in Christ and in the Church, which entails adherence to the truth of the Gospel.”[26]
‘Signs of courageous hope’
Part of the traditional address to the Diplomatic Corps was a reflection on areas of concern around the world, including the Holy Land, Ukraine and Venezuela. Pope Leo XIV also pointed out “signs of courageous hope” in the world, including the lasting peace between Bosnia and Herzegovina, and steps toward peace between Armenia and Azerbaijan.
While not explicitly offered as a sign of hope, Pope Leo began his address by noting signs of hope within the life of the Church over the past year, including the Jubilee of Hope, which was a time of joyful cooperation between the Holy See and the Italian Republic; the prayerful mourning for Pope Francis, in the hope of his “return to the Father’s house”; and the 1700th anniversary of the Council of Nicea as an opportunity “for renewing our commitment to the journey toward the full visible unity of all Christians.”[27]
In terms of hope, Pope Leo also concluded his address with an appeal for the imitation of Saint Francis of Assisi, the second great saint of the address. In this Franciscan Jubilee Year, Pope Leo urges all persons of good will to make their own the great saint’s “courage to live in truth,” with “humble hearts turned toward the heavenly city.”[28] The example of il Poverello is a reminder that “courageous signs of hope” are still possible in the present time.
It is sometimes said that Christ proclaimed the Kingdom of God and what came forth was the Church. Such claims are cynical insofar as they imply that the Church is not working for the kingdom of God, and naive insofar as they seem to forget the nature of the Church, as spouse of Christ, and that God’s work proceeds in time and with the help of humans in their common life together.
With respect to the slow work of God in cooperation with humanity, in his May 2025 address to the Movements and Associations of the “Arena of Peace” in Verona, Pope Leo made a connection between peace and subsidiarity and solidarity. He thus underlined an important precondition for effecting such signs of hope. As he told those gathered, “If you want peace, prepare institutions of peace. Increasingly we realize that this cannot simply involve political institutions, whether national or international, but requires all institutions – educational, economic and social.”[29] This is a challenge of solidarity, what Pope Francis called “the need to pass from ‘I’ to ‘we’,” and also that of subsidiarity, with the call to establish healthy forms of associational life that can cultivate and support the virtues of persons as citizens and Catholics, and enable their common life together for peace.[30]
These considerations are in line with the message of the pope to the diplomatic corps: peace is a difficult good, but indeed realistic. To avoid the task of peace is to avoid what makes us human. To seek it is ultimately to become fully alive in Christ.
The Church
As noted above, Pope Leo reminded diplomats in his encounter with them on January 9, 2026, that the Holy See’s diplomatic activities are shaped by a fundamental disposition: to be “not strangers to the political world,” but rather to, “guided by the Scriptures, seek to apply Christian ethics to civil government.”[31] The traditional Libertas ecclesiae, in other words, does not mean that the Church seeks privilege or status, but rather the commitment of the Church to serve the world, to attract it to Christ, the light of the nations.[32]
Since at least Vatican II and Lumen Gentium, the popes have been at pains to emphasize that the Church is not primarily an institution, which feature is always secondary to its character as a mystery, as a sacrament. If a distinctive feature of Pope Leo’s ecclesiology has emerged, it is the insistence, in this address and elsewhere, that the institutional features of the Church nevertheless do matter and do require attention, and precisely to better render them for the service of that mystery. Pope Leo has put the institutional capacities of the Catholic Church at the service of peace, for example, by urging leaders of other religious communities to join in the search for peace.
In calling for religious freedom for all persons, the pope thus seeks to protect the right and duty of all persons to contribute to the common good through their own traditions as “a reflection of the one divine Mystery that embraces all creation.”[33] Finding fraternity among people of diverse creeds, he told a group of ecumenical and interreligious leaders in May 2025, “will certainly contribute to building a more peaceful world.”[34]
A characteristic of Pope Leo’s teaching emerges from this address, one again in deep harmony with the teaching of Leo XIII.[35] In clarifying the roles of the Church and the family, the pontiff clarifies the role of the state. The state, after all, must recognize its limits and basis: the family exists before political authority, and the Church points toward a world beyond the present one. Pope Leo offers such wisdom not only to delimit the state, however, but also to renew its mission and purpose in the world. He further indicates throughout the possibilities for a renewal of subsidiarity: those places where citizens are called to substantial initiative.
For all that is novel in late modern politics, in other words, much remains the same. The challenges of politics are fundamentally moral and anthropological. Just as Christians cannot leave morality behind in entering into politics, so their entry into international relations and multilateral politics does not replace the slow, hard work of politics with technocratic paradigms. The truth about God, humanity and creation retains its power across all of these orders.
Pope Leo’s address puts on display some of the deepest foundations of Catholic teaching on matters of public life. He thus invites all people of good will to seek for the deepest truths about themselves, human society, and ultimately God. To recall the Conciliar declaration Dignitatis Humanae, “all are bound to seek the truth, especially in what concerns God and His Church, and to embrace the truth they come to know, and to hold fast to it.”[36]
In a world in which the demands of truth and love can seem opposed, the pope emphasizes that truth is fundamentally an encounter with love itself. And of course, that love is the Logos, which is to say the one true Word.
Reproduced with permission by La Civilta Cattolica.
DOI: https://doi.org/10.32009/22072446.0426.11
[1]. Cf. G. Cucci – M. G. Portoso, “A Disarmed and Disarming Peace”, in Civ. Catt. English Edition December 2025 (laciviltacattolica.com/a-disarmed-and-disarming-peace/); C. R. Altieri, Leo XIV: The New Pope and Catholic Reform, London, Bloomsbury Continuum, 2025.
[2]. Cf. Leo XIV, Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[3]. Ibid.
[4]. “Ubi solitudinem faciunt, pacem appellant” (Tacitus, Agricola, 30, 4). The phrase is attributed to Calgacus.
[5]. Leo XIV, Audience for the Diplomatic Corps accredited to the Holy See, May 16, 2025.
[6]. Id., Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[7]. Ibid.
[8]. Ibid.
[9]. Id., Message for the 59th World Day of Peace, January 1, 2026.
[10]. Id., Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[11]. Id., Message for the 59th World Day of Peace, January 1, 2026.
[12]. Id., Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[13]. J. Maritain, “The End of Machiavellianism”, in The Review of Politics 4 (1942/1), 1-33; cf. L. Strauss, Thoughts on Machiavelli, Glencoe, IL, The Free Press, 1958, 11-14.
[14]. Leo XIV, Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[15]. Ibid.
[16]. Ibid.
[17]. Ibid.
[18]. Ibid.
[19]. Id., Audience for the Diplomatic Corps accredited to the Holy See, May 16, 2025.
[20]. Id., Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[21]. Ibid.
[22]. Ibid.
[23]. Cf. Francis, Apostolic exhortation Laudate Deum, October 4, 2023, nn. 34-43; Id., Encyclical Fratelli Tutti, October 4, 2020, nn. 154-197.
[24]. Leo XIV, Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[25]. Id., Address to the Prelates of the Roman Rota on the occasion of the inauguration of the judicial year, January 26, 2026.
[26]. Ibid.
[27]. Id., Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[28]. Ibid.
[29]. Id., Speech to the movements and associations behind the ‘Arena of Peace’ (Verona), May 30, 2025.
[30]. Cf. C. R. Altieri, Leo XIV …, op. cit., 84-5.
[31]. Leo XIV, Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[32]. Cf. Id., Address to the Extraordinary Consistory, January 7, 2026.
[33]. Leo XIV, Address to the Diplomatic Corps accredited to the Holy See, January 9, 2026.
[34]. Id., Address to the Representatives of other Churches, ecclesial communities and other religions, May 19, 2025.
[35]. Cf. W. McCormick, Before ‘Rerum Novarum’, five social encyclicals of Pope Leo XIII, in Civ. Catt English Edition October, 2025 (laciviltacattolica.com/before-rerum-novarum-five-social-encyclicals-of-pope-leo-xiii/).
[36]. Second Vatican Council, Declaration Dignitatis Humanae (December 7, 1965), no.1.
