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Religion & Liberty: Volume 34, Number 1

Catholicism and Slavery: Setting the Record Straight

    It’s easy to forget that the institution of slavery has constituted a social norm in human history. From the grand perspective of time, its supporters and defenders have far outnumbered its critics and condemners.

    The Catholic Church is often chastised for tolerating, even promoting, slavery as Catholic nations expanded their empires into Africa and the New World. But a fair reading of the evidence shows that the Church was more often on the side of the angels—and the enslaved.

    The Worst of Indignities: The Catholic Church on Slavery
    The Worst of Indignities: The Catholic Church on Slavery
    By Paul Kengor
    (Emmaus Road, 2023)


    While one can find intimations of unease with slavery in some Greek and Roman thinkers, there is little question that it was Christianity that introduced the deepest doubts about both the legitimacy of slavery as a practice and the widespread cultural habit of viewing entire categories of people as natural slaves.

    This runs against the common narrative that it is only with the various Enlightenments that slavery was subsequently challenged. With some notable exceptions, Enlightenment thinkers were either silent on the topic or decidedly ambiguous. In fact, the institution that most often was the target of many Enlightenment thinkers—the Catholic Church—turns out to have been consistent and early in its condemnation of slavery.

    Knowledge of Catholicism’s firm stance against slavery is not widespread, even among Catholics, some of whom hold senior positions in the Church today. I was reminded of this recently when reading Pope Francis’ response to questions submitted by five cardinals in July 2023: specifically, the part in which the pope addressed the broad topic of the magisterium’s interpretation of Scripture and its own previous statements. Referring particularly to Pope Nicholas V’s bull Dum Diversas (1452), Francis describes this as a magisterial document “that tolerated slavery,” and thus a text that “requires interpretation.”

    Enter a new and very timely book, The Worst of Indignities: The Catholic Church on Slavery. Its author, Paul Kengor, addresses the topic of Dum Diversas and another of Nicholas V’s bulls, Romanus Pontifex (circa 1454), at the book’s very beginning. Like any good scholar, Kengor analyzes the two texts carefully and consults serious commentators on the topic. This leads him to two conclusions.

    The first is that one needs to understand the context of both documents. One is the treatment of captives taken during war at a time in which the customs and rules surrounding this topic, especially as expressed in the law of nations, were then being debated. This was a period in which, Kengor notes, “the notion of ‘just’ enslavement was accepted as a form of punishment for dealing with wartime prisoners in a just war.” Other scholars also observe, Kengor points out, that Nicholas V was addressing a particular situation (Portugal’s expansion into West Africa and subsequent conflict with pagan and Muslim populations). The pope’s comments, one cited scholar states, were “not meant to apply to all times and places.”

    Kengor’s second conclusion is that, even putting the worst interpretation upon these two documents (which, Kengor admits, might yet be accurate), we should bear in mind that these statements

    were utter exceptions, completely anomalous to other popes, clergy, lay leaders, and Church councils over two millennia—that is, immediately before, immediately after, and ever since. Any modern scholar who seeks to elevate those two statements above and beyond everything else is being grossly unfair. That would not be scholarly.

    Much of Kengor’s book subsequently explains the “before,” “after,” and “ever since” of the Catholic Church’s condemnation of slavery and how this teaching emerged very early in the Church’s life. Alongside exploring the history of the teaching, Kengor addresses how Catholic bishops, priests, religious orders, and laypeople treated slaves. In other words, ideas and praxis are given equal attention.

    On the level of formal teaching, the Church’s record, Kengor illustrates, is one of consistent opposition to slavery. Very quickly, slavery was understood to be sinful by the Church. The position emerged more or less directly from the Gospels and the writings of Saint Paul. It was also considered universal in its application.

    The institution of slavery has constituted a social norm in human history.

    This last point matters because a few scholars have argued that the Church was opposed only to the enslavement of Christians, whether by Christians or non-Christians, the implication being it was acceptable to enslave non-Christians. Certainly, some statements by popes and councils refer explicitly to Christians, but the omission of references to non-Christians is not intentional. For one thing, most church documents on slavery refer to the wrongness of enslaving anyone. It is also the case that statements about enslaving Christians by popes like Eugene IV were accompanied by other documents composed by the same popes “that addressed the welfare of all people.”

    In making his argument, Kengor analyzes a formidable amount of material to demonstrate the consistency of official Catholic magisterial teaching on the inherently evil nature of slavery. Especially concise statements were issued by the Holy Office (today’s Dicastery for the Doctrine of the Faith) in the 17th century. These spelled out in question-and-answer format not only the wrongness of slavery itself but also the obligation of captors, buyers, and owners of slaves to free and compensate them. There is no mention of the guilt and responsibility of anyone involved in the slave business being diminished by cultural, psychological, or sociological factors that might affect their personal culpability for their actions.

    Catholic teaching on slavery, Kengor also illustrates, was “far ahead of the world.” Though it is politically incorrect to say so, Kengor underscores that slavery simply was not questioned in any meaningful way in pagan Europe or pre-Christian cultures in North America, Latin America, Africa, and Asia. At a time in which there are tendencies to idealize such cultures—or even deny that brutal things like mass slavery and human sacrifice occurred in Mesoamerican cultures—these truths bear repeating.

    Formal teaching, however, is one thing. Practice is another. Kengor does not shy away from acknowledging that numerous Catholics throughout history have failed to acknowledge and embrace Catholic teaching on slavery. Bishops, priests, and male and female religious orders purchased, owned, and sold slaves at different points of history. Kengor highlights, for instance, how the Society of Jesus (the Jesuits) owned slaves in pre-colonial and pre–Civil War America: something for which the Jesuits and other Catholic religious orders have since apologized.

    An excavated tzompantli displaying sacrificial victims at the Templo Mayor in modern-day Mexico City
    (Photo by Juan Carlos Fonseca Mata / Wikipedia)

    In one sense, the fact of such practices is disturbing. In another sense, however, there is nothing extraordinary about these facts. Every Catholic, including those formally declared to be saints, has sinned. There have also been plenty of Catholics who have decided that the Church’s magisterial teaching somehow doesn’t apply to them, or who have quietly (or loudly) dissented from church teaching.

    But for every Catholic who has denied that certain sinful acts are indeed evil and never to be done, there are those who have not only firmly held to church teaching on such matters but also sought to see its implications realized in practice. That includes working to ameliorate the effects and workings of slavery and striving for its abolition.

    In many cases, this was reflected in the decision of those who, having converted to Christianity, made the decision also to free their slaves. Some clergy worked strenuously to redeem slaves, often going to slave markets, where captives from war or raids were being auctioned off, to buy them and then immediately set them free. Sometimes high church officials directly confronted Christians engaged in practices associated with slavery. A good example is Pope St. Gregory III’s decision to issue a prohibition against Christians who persisted “in selling their slaves to pagans for sacrifices.”

    This emphasis upon the practical work of liberating slaves eventually assumed institutional form. By the beginning of the second millennium, entire religious orders were being created for the primary purpose of emancipating slaves. St. John of Matha (1160–1213), for instance, founded an order in 1198 dedicated to ransoming Christians who had been kidnapped and sold into slavery by pirates of the Barbary Coast. Such work—much of which was dangerous and often cost the lives of monk-liberators—continued for centuries. The effectiveness of these activities often involved avoiding direct confrontation with enslavers, which would have undermined the ability of such individuals and religious orders to rescue people from servitude.

    Then there were the intellectual battles carried out by theologians who fought efforts to produce rationalizations for the enslavement of peoples. Spanish policy toward the native peoples of the Americas is a case in point. Missionaries in modern-day Haiti and the Dominican Republic, for example, openly preached against the harsh treatment of these peoples by their Spanish masters.

    This was followed by the growth of an entire network of Catholic thinkers, epitomized by the Dominican theologian Francisco de Vitoria, who came to the defense of the native peoples and employed the only tool they had—the natural law tradition—to affirm the intrinsic dignity of the natives, and therefore all the rights that flowed directly from that dignity. This involved engaging in intense debates with other Catholic theologians who sought to revive the Aristotelian idea of natural slavery to justify the Spanish conquerors’ dispossession of the native people’s lands.

    Some clergy worked strenuously to redeem slaves, often going to slave markets to buy them and then set them free.

    But the most moving part of Kengor’s book is his account of the lives of three former slaves of the modern era. One of them, Josephine Bakhita (1869–1947), a convert to Catholicism, has been declared a saint. The other two, Pierre Toussaint (1766–1853) and Augustus Tolton (1854–1897), have been accorded the title of “venerable,” meaning that their heroic virtue has been formally recognized by the Church.

    Kengor does not soft-peddle the impact of slavery on these three people, however. The details of St. Josephine Bakhita’s early life are especially harrowing. In each case, it should be noted, they chose neither the path of bitterness and vengeance nor that of self-destruction. Instead, they embraced the Christian faith in all its fullness and showed that, despite having been enslaved, living the Christian life is no mere “ideal” but something that everyone is capable of realizing.

    Toward the end of his book, Kengor draws attention to Pope Francis’ powerful statements against slavery in the modern world, whether it is human trafficking or the older forms of slavery that persist in many parts of the world today. Kengor also notes, however, that Pope Francis apparently does not have a good grasp of the Church’s long history of opposition to slavery. In his 2020 encyclical, Fratelli Tutti, for instance, Francis comments, “I sometimes wonder why, in light of [the manifest evil of modern slavery], it took so long for the Church unequivocally to condemn slavery and various forms of violence” (FT 86).

    As Kengor states, this “is a disappointingly inaccurate claim for a Roman Catholic Church that commendably condemned slavery earlier than essentially every existing country, culture, and institution.” That negative judgment on slavery was based squarely on the inner logic of what Christ ultimately reveals about the nature, dignity, and ultimate end of the human person. It also has nothing in common, Kengor stresses, with contemporary secular liberationist movements grounded in ideologies like identity politics, intersectionality, and critical race theory, all of which mimic the claims of revealed religion.

    In the end, the Christian condemnation of slavery is rooted firmly in the idea, so beautifully expressed in the Hebrew Bible and the New Testament, that all peoplewhatever their sex, ethnicity, or faith—are made in the image of God (imago Dei). This means every single one of us is a seamless integration of materiality and spirit that includes reason and free will. That common image-bearing nature not only makes our enslavement of other people unthinkable; it is also central to our capacity to resist that other form of enslavement: the slavery to sin and evil from which Christ came to liberate us.

    Dr. Samuel Gregg is an affiliate scholar at the Acton Institute, and serves as the the Friedrich Hayek Chair in Economics and Economic History at the American Institute for Economic Research.

    He has a D.Phil. in moral philosophy and political economy from Oxford University, and an M.A. in political philosophy from the University of Melbourne.

    He has written and spoken extensively on questions of political economy, economic history, monetary theory and policy, and natural law theory. He is the author of sixteen books, including On Ordered Liberty(2003), The Commercial