If you haven’t noticed, the term “Catholic Social Teaching”—or simply CST—is in common usage these days. Scholars and pundits representing all points on the ideological spectrum have laid claim to CST in recent years, but few ordinary Catholics are familiar with the primary source documents that comprise this extraordinary body of teaching. That’s a pity because none of them are overly technical or dense; on the contrary, they are all easy to read, applicable to the real world, and chock full of common sense.
Since CST represents a development of certain themes over time, it’s better to start at the beginning and work forward. Here’s a useful five-pack for kicking off your exploration of CST, with recommendations at the end for rounding out this self-study project.
Rerum Novarum (“Of New Realities”), Encyclical Letter of Pope Leo XIII, 1891. The release of Rerum Novarum marked the beginning of modern social teaching. It was the first serious attempt by the Church to answer the twin challenges of capitalism and socialism, clearly identifying ways in which the Christian humanism of the Church could blunt the excesses of each. In Rerum Novarum, Pope Leo affirmed both the natural right to private property, as well as the dignity of labor and the right of workers to organize. He acknowledged as a natural fact the unequal distribution of talent in society, but insisted on the equal worth of persons. And he recognized the role of government in safeguarding the common good—which he linked to the condition of the poor—while prescribing limits on government power. Last, he asserted the Church’s right to teach on political and economic matters. In many ways, all Catholic Social Teaching since 1891 has been a commentary on Rerum Novarum.
Quadragesimo Anno (“After Forty Years”), Encyclical Letter of Pope Pius XI, 1931. The title refers to the anniversary of the publication of Rerum Novarum. In this letter, Pope Pius returned to many of the themes raised earlier by Pope Leo, but sharpened his focus in ways that both pleased and annoyed socialists and capitalists alike. He inveighed against a collectivism that would destroy the individual nature of property rights and undermine the dignity of the person, but also asserted that the right to private property is not absolute, and decried the manner in which concentrations of wealth crush free markets and make a “slave” of the state. He called for just wages that would enable workers to become owners, and described what we now call the principle of subsidiarity. In Quadragesimo Anno, Pope Pius’s condemnation of socialism—not social democracy—was categorical, but his practical criticism of capitalist exploitation was equally harsh.
Mater et Magistra (“Mother and Teacher”), Encyclical Letter of Pope St. John XXIII, 1961. Written in observance of the 70th anniversary of Rerum Novarum, Mater et Magistra extended CST to the task of international development at a time of widespread decolonization following the Second World War. New states were appearing across the globe, many of them struggling from the legacy of colonialism: economic exploitation, weak or nonexistent civil society, a lack of experience in democratic forms of government, and so on. Pope St. John restated the by-now consistent themes and principles of CST, but applied them from a global perspective. He advocated a just international economy based on cooperation, development and human rights. He specifically noted the responsibility of wealthy nations to provide monetary and other assistance to nations struggling with widespread poverty. Perhaps as important, he disabused his readers of the notion that CST was a merely optional expression of the Faith: “We must reaffirm most strongly,” he wrote, “that this Catholic social doctrine is an integral part of the Christian conception of life” (#222).
Pacem in Terris (“Peace on Earth”), Encyclical Letter of Pope St. John XXIII, 1963. The papacy of Giovanni Roncalli coincided with the height of Cold War tension. The Church was not a neutral party in the contest between the Soviet bloc and the West, but its priority was achieving a just and lasting peace. In Pacem in Terris, the Holy Father begins with a meditation on order—in the universe, in human beings, and between human beings. He describes social order as a harmony between rights—social, political, economic, legal—and duties. This harmony applies not only to individuals, but also to groups within society, and public authorities themselves. Preserving this balance, the Pope insists, is the ground for peaceful and just cooperation within society and between nations. The relationships between states, the Pope writes, “must likewise be harmonized in accordance with the dictates of truth, justice, willing cooperation, and freedom.” He goes on to address issues that affect this harmony, including the arms race, and calls for “thoroughgoing and complete” disarmament.
Gaudium et Spes (“Joy and Hope”), Pastoral Constitution on the Church in the Modern World, Second Vatican Council, 1965. Perhaps the most important of all the documents that make up CST, Gaudium et Spes has to be read, and read slowly, to be appreciated. The breadth of the document is remarkable, encompassing Church teaching on the human person and social life, the relation of the Church to the secular world, marriage and the family, technology and culture, the economic and political order, peace and international relations. It is no accident that in his magisterial writings, Pope St. John Paul II cited Gaudium et Spes hundreds of times, perhaps more often than any other single non-biblical source. Nearly all of the themes we identify with CST today, from the life and dignity of the human person to the care of creation, are present in developed form in Gaudium et Spes.
The Catholic reader who consumes these five documents will find himself better equipped to move on to the social encyclicals of the post-conciliar Church. That suite of documents would include Pope Paul VI’s Populorum Progressio (1967) and Octogesima Adveniens (1971); Pope St. John Paul II’s magnificent works, Laborem Exercens (1981), Solicitudo Rei Socialis (1987), Centesimus Annus (1991), and Evangelium Vitae (1995); and Pope Benedict XVI’s Caritas in Veritate (2009). And, of course, there’s the Compendium of the Social Doctrine of the Church, commissioned by Pope St. John Paul II and published in 2004.
is a partner at PathTree, a consulting firm focused on organizational resilience and strategy. He also serves as president of both the Society of St. Vincent de Paul, Diocese of Providence, and a local homeless shelter and soup kitchen. Mark is the author of Forty Days, Forty Graces: Essays By a Grateful Pilgrim. He and his wife Camila have been married for 30 years and they have two adult children.