It is sixty years since Pope John XXIII's encyclical "Pacem in Terris - Peace on Earth". The encyclical remains highly topical, for in a world waging numerous wars, such as the one in Ukraine, marked by terrorism, the emergence of viruses, problems of food and water, an arms race and the renewed threat of nuclear war, together with various other negative social phenomena, it is peace itself, at every level, that is endangered – peace on earth in general. It had been expected that after the fall of the Berlin Wall in 1989, the symbol of the division between East and West, a new period of peace would follow, marked by general security and free of the danger of nuclear war. Yet these very days show something quite the opposite. The threat is growing to the point of unpredictability, since nuclear weapons, and the real danger of their use, have once again become part of our everyday life. Carl Gustav Jung outlined this well long ago: "Only let sufficient corresponding material (weapons) pile up, and the diabolical element in man will infallibly be strengthened, and set out on the march with him."

"It is almost impossible to think that in the atomic age war could still be used as an instrument of justice," wrote John XXIII, using the Latin phrase "alienum est a ratione" – to think of war as a solution to conflict is "unreasonable". He advocates dialogue between people who differ ideologically or in other ways, and cooperation in mutually beneficial undertakings "among all men of good will".

Pope John XXIII was born in the village of Sotto il Monte, in the province of Lombardy, on 25 November 1881. That same day, his mother Marianna and his father Giovanni carried him to church and had him baptised, giving him the name Angelo Giuseppe. He was the first boy born to the Roncalli family, though the fourth child in order, out of thirteen children in all. They lived, together with their six cows, on the first floor of a house shared with thirty-two close relatives. Of his family he would later say, in a letter to his parents: "Since I left home, I have read many books and learned many things that you could not have taught me. But what I learned from you remains the most precious and the most important of all, and it sustains and gives life to the many other things I have learned since, over so many years of studying and teaching."

Already as an eleven-year-old boy he went to the nearby seminary in Bergamo. After studying theology, he was called up for military service in Rome: "Oh, what a swamp the army is, from which rot flows out to flood the city with its stench. Who will be saved from this dreadful mire, if God does not help?"  The upheaval of the First World War (194–1918) did not pass young Angelo by either; in duty to his homeland he was called up as a medical NCO in military hospitals in northern Italy. After he became Pope, during an audience for military chaplains, he confirmed that this service had "amid the groans of the wounded and the sick, spurred me on to a universal longing for peace, the highest good of humanity. Never, as then, did we feel how great is man's desire for peace."

During the Second World War (1939–1945) he engaged in charitable work, helping everyone, especially Jews. He writes to his family: "Think of those who are at war, poor souls! So many questions pass through my hands, from parents, spouses, children, seeking news of their own who have been killed, taken prisoner or gone missing. To die in war, by violence, to die for one's homeland – and that out of obedience, out of love for one's brothers – is a precious act, a cry raised to the Lord's mercy. I believe that in the end our beloved homeland will come safely through this war, terrible though it is. War is dreadful, a dreadful plague. Blessed are we Catholics, who find in religion all that is needed to enliven our patriotism too, and in religion we seek no excuse to impose ourselves on anyone, but rather an incentive to respect everyone and spread a sense of true brotherhood, and so make ourselves loved. And the war will pass: and when it passes, we shall be convinced that the Lord did not sleep during the war, nor was He deaf to the many prayers of good and innocent souls…" In Journal of a Soul he writes: "The weeping of nations. It reaches my ears from every corner of Europe, and from beyond it too. This deadly war, which lays waste the earth, the seas and the skies, is nothing but the vengeance of divine justice, because men offend against and break the sacred ordinances that justice has given to human society. War is willed by men, with their eyes open, against all the most sacred laws. Whoever starts it and abets it is always "princeps huius mundi" (the prince of this world), who has nothing in common with Christ, who is the "prince of peace". And when war blazes up, nations have no choice left but repentance and surrender to the Lord's mercy, that it may prove stronger than justice, and that through abundant grace it may bring the powerful of the world to their senses and lead them back again to peace."

Through the last months of the war and the first months of peace he helped prisoners of war, and also concerned himself with normalising Church life in France. The historical circumstances after the end of the Second World War continued to run in the channel of the war that had just ended. The conflict took on a different dimension of tension, manifested in the strained relations between the Eastern and Western blocs. This was the era of the so-called Cold War (1945–1991). In an address to the UNESCO General Conference on 11 July 1951, Roncalli summed up his teaching in a single sentence: "For all people of good will, the sense of brotherhood that shines on the face of every human being is a reflection of the face of God." As Pope he took the name John XXIII, and his papal motto was "Obedience and Peace".

Soon Nikita Khrushchev and the American President John Kennedy came into conflict over Cuba. The world once again found itself on the brink of a Third World War. The Pope again took the initiative and issued an appeal, in the name of the whole world, for world peace. The Soviets backed down, and the world was able to breathe again. To all Christians he sent this message: "Let us seek what unites us, not what divides us."

Through Vatican Radio the Pope addressed the Western allies and the Soviets, calling on them to preserve peace. Particularly significant were his words in his sincere appeal to the world's rulers to prevent a nuclear catastrophe during the Cuban crisis of October 1962: "Peace and brotherhood among men matter more to the Church than anything else. In this regard, we have recalled the grave duties of those who bear the responsibility of government. Today we renew this heartfelt appeal, and we call upon heads of state not to remain unmoved by this cry of humanity. Let them do everything in their power to save peace: in this way they will spare the world the horrors of a war whose terrifying consequences no one can foresee. Let them, with full responsibility, hear the anxious cry that rises to heaven from every corner of the earth, from innocent children to the aged, from individuals and communities alike: PEACE! PEACE! Today we repeat this solemn appeal. We ask all who govern not to remain deaf to this cry of humanity. Let them do everything within their power to save peace. In this way they will free the world from the horrors of war, whose terrible consequences no one can foresee. Continue the negotiations. Yes, this loyal and open disposition has great value as a witness before everyone's conscience and before history. To promote, encourage and accept negotiations, at every level and at every moment, is a rule of wisdom and prudence which calls down the blessing of heaven and earth." It was as though he wished to make known, especially to Christians, what he himself was living through and feeling, and what he recorded and expressed in his Journal of a Soul: "The whole world is my family."

The Soviet leader Nikita Khrushchev responded in Pravda, praising the Pope's appeal: "The concern the Pope shows for peace…, his appeal is a good sign. Since in our age there exist the most destructive means for the annihilation of the human race, it is impermissible to gamble with the fate of nations." Only a few weeks later Khrushchev sent the Pope a message of congratulations on his 80th birthday. The crisis was brought to an end thanks to the Pope: "Today I feel something moving, something that lightens my soul. The word of the Gospel is not silent. It echoes from one end of the world to the other and finds its way to hearts. Dangers and sorrows, human prudence and wisdom, must all flow together into a single hymn of love…Throughout the whole world there is an effective desire for building up and renewal, so that heavenly light may shine ever more brightly over mankind."

Only a few months after the Cuban crisis, the Good Pope published the encyclical Pacem in Terris (Peace on Earth), on Maundy Thursday 1963, in which he addressed the whole human race, appealing for world peace in the face of the threatening nuclear catastrophe, stressing that building peace is the concern of everyone – individuals and nations alike – and quoting the words of his predecessor Pius XII: "Nothing is lost by peace. Everything may be lost by war." It is interesting that the encyclical Pacem in Terris, admittedly only in some parts, was published even in the USSR of the time, in the magazine Za Rubezhom, and that it was published in full by a newspaper otherwise very unfavourable to the Church, The New York Times. Never afterwards was any Catholic encyclical again published in that newspaper.

Of course, that crisis reminded the world of the possibility of global annihilation by nuclear weapons, in the absence of dialogue and goodwill on both sides of the so-called Iron Curtain. The trampling of the human being on any grounds at all leads, in every age, to a deep crisis of culture and civilisation, and indeed of meaning itself. Even today many remember the Pope's words: "Life is a pilgrimage. We are made for heaven. Here on earth we pause for a short time, and then continue the journey." In that encyclical, John XXIII expresses a message still relevant today: "Violence has never done anything but tear down, never build up; it has inflamed passions, never calmed them; it has piled up hatred and ruins, never reconciled the estranged; it has cast men and parties into the harsh necessity of slowly, after painful experience, building anew upon the ruins left behind by discord."

The Catholic vision of peace consists of four factors: human rights, development, solidarity and world order. But peace on earth is not merely the absence of war, or the successful avoidance of war; it is the true realisation of human dignity across the whole planet.

He stresses that the foundation of world peace must spring from the recognition of rights and duties. Peace is the task of all people of good will who believe in truth, in justice, in love and in freedom – these are words from the last encyclical of St John XXIII, addressed to all people of good will at a moment when the international community seemed to be heading towards a third world war. Four main points are highlighted for guiding humanity onto the path of peace: the central place of the person, inviolable in his rights yet also bound by duties; the common good, which must be sought and realised everywhere; the moral foundation of political community; and the strength of reason together with the beacon of faith.

Focused on the theme of the avoidance of war and the building of paths to peace – that great aspiration of human beings – the encyclical came to light in a period of tension and Cold War. Its message is powerful: peace remains mere words unless it is founded on an order grounded in truth, built up in accordance with justice, given life and made whole by love, and realised in freedom: "Truth will build peace if all individuals sincerely acknowledge not only their rights, but also their duties towards others. Justice will build peace if, in practice, we all respect the rights of others and fulfil our obligations towards them. Love will build peace if people feel the needs of others as their own and share what they have with others. Freedom will build peace, and make it fruitful, if, in choosing the means to that end, people act in accordance with reason and accept responsibility for their own actions."

It is interesting that The New York Times published the encyclical Pacem in Terris in full, which was the first such case. In the United States, the following year (1964), the awarding of a prize called the Pacem in Terris Peace and Freedom Award also began.

At the very start of the encyclical, John XXIII delivers a decisively "striking" message, one increasingly at odds with today's mentality: "Peace on Earth – which man throughout the ages has so longed for and sought after – can never be established, never guaranteed, except by the diligent observance of the divinely established order." It is Pope John XXIII's position that peace on earth can be established only if there is a right order between individuals, between states and within them, and among all people. These relations must be grounded in the fact that "every human being is a person" and that, as a person, he "has rights and duties, which together flow as a direct consequence from his nature. Just as we cannot judge the general good of individual countries without taking account of the human person, so likewise we cannot judge the general good of all nations." The common good, says John XXIII, is "the objective recognition, preservation and promotion of all the rights of the human person." Yet in doing so, one must not forget the extremely important fact "that the common good touches the whole man, that is to say the needs both of his body and of his soul."

In Pacem in Terris, John XXIII systematically sets out and describes a whole series of human rights. First of all there is the right to life and, connected with it, the right to a proper standard of living. Furthermore, important are the rights relating to moral and cultural values: "Man has a natural right to be respected, to have his good name respected, to freedom in investigating the truth and, within the limits of the moral order and the common good, to put forward and spread his opinions, to cultivate any art he pleases; finally, to be accurately informed about public events." John XXIII also cites a right in the religious sphere: "Also among man's rights is that of being able to worship God in accordance with the right dictates of his own conscience, and to profess his religion both in private and in public." Particular emphasis is given to the right connected with the family, "founded upon marriage," which, most importantly, "must be regarded as the natural, primary cell of human society." The encyclical also gives special emphasis to the right to work and the rights that flow from it: "We shall not pass over in silence the worker's right to a wage determined according to the demands of justice, which (…) must allow him a way of life in keeping with human dignity." Sadly, in the developed industrial states, millions of people who would like to work today cannot find employment.

John XXIII pays particular attention to relations between peoples (states), which "must be regulated by truth, justice, willing solidarity and freedom," that is, "the same natural law which governs the life and conduct of individual citizens must also govern mutual relations between states." Sadly, John XXIII observes, there is a tendency to try to preserve world peace through the production and stockpiling of weapons. He therefore appeals for the arms race to cease, "since true and firm peace among nations does not consist in a balance of arms, but in mutual trust." This requires that "in place of the supreme principle on which peace today rests, an altogether different one be put forward, one which would establish that the firmness of true peace among nations lies not in equal armed strength, but solely in mutual trust."

The concluding thought of the encyclical Pacem in Terris runs: "Now the order which prevails in human society is wholly incorporeal in nature. Its foundation is truth, and it must be brought into effect by justice. It needs to be animated and perfected by men's love for one another, and, while preserving freedom intact, it must make for an equilibrium in society which is increasingly more human in character." But "peace is an empty word," says John XXIII, "if it does not rest upon the order which this encyclical has outlined in broad lines." To this can only be added the words of Jesus: "Blessed are the peacemakers, for they shall be called sons of God" (Mt 5:9). 

It later turned out that this was, in a sense, his testament. Rumours grew ever more frequent that the Pope was gravely ill (stomach cancer) and would not live much longer. The Pope responded to these reports in a way that was entirely his own: "My bag is packed. I am ready." He did not live to see the close of the Second Vatican Council. He died on 3 June 1963. He was buried in the crypt of St Peter's Basilica. Pope John Paul II declared him blessed in 2000, and Pope Francis, on 27 April 2014, together with Pope John Paul II, declared him a saint.