The Church ended slavery. So why is Leo XIV apologizing?

(LifeSiteNews) – In Leo XIV’s new encyclical Magnifica Humanitas, given on May 15, 2026 (“On safeguarding the human person in the time of Artificial Intelligence), he asked for “pardon” for the Church having taken “eighteen centuries” to recognize the “full incompatibility” between slavery and “the dignity of every human being” – and the “suffering and humiliation” this has caused.

In paragraph n. 176, Magnifica Humanitas criticizes some contemporary labor conditions as a kind of slavery before stating that:

In continuity with the tradition inaugurated by Leo XIII, the Church renews her firm condemnation of all forms of slavery, trafficking and the commodification of persons. (fn. 175)

However, the encyclical claims that “the Church has gradually come to a deeper awareness of the gravity” of slavery, and related issues, and describes this as a “development of her doctrine.”

The encyclical laments “the delay with which both society and the Church came to denounce the scourge of slavery” and states that “there was not always consistency in practice – given that slavery was long tolerated before being unequivocally condemned.” This is because, it says, “the moral criteria that matured over time” were not “available” to the Church in previous ages.

The explanation offered for this “delay” appears in one of the footnotes:

Political and, at times, even economic needs overcame the demands of the Gospel. The need for evangelization was frequently compromised or at least misunderstood with regard to the needs of worldly powers, thus relativizing the problematic incompatibility of slavery with the Christian conscience. (fn. 174)

Another footnote states that “as late as 1866, the Holy Office distinguished between the immoral and moral aspects of slavery, without fully condemning it.”

“It was only in the nineteenth century,” the body of the encyclical states, “that a formal, absolute and universal condemnation of slavery was clearly articulated” by Pope Leo XIII. It adds, however:

(T)here has been a continuous affirmation throughout history of the dignity of every human being, created in the image of God, even if it took eighteen centuries for its full incompatibility with slavery to be explicitly recognized.

The “delay,” it says, “constitutes a wound in Christian memory, one from which we cannot consider ourselves detached.” It is for this reason, and the “immense suffering and humiliation endured by so many in contrast to their immeasurable dignity as persons infinitely loved by the Lord,” that Leo XIV writes:

(I)n the name of the Church, I sincerely ask for pardon.

The issues with this are as follows:

• The Church was responsible for the progressive eradication of slavery, and a society in which socio-economic conditions were so radically improved that slavery became obsolete
• The term “slavery” is equivocal and encompasses a broad range of practices: traditional Catholic doctrine holds that the institution itself is an evil suffered and to be ended, and (to put it mildly) far from the ideal of how humans should live; but that, while some of the practices denoted by the term are indeed intrinsically evil, others are not
• The Church condemned intrinsically evil forms of slavery and worked to render slavery obsolete long before the 19th century
• While Pope Leo XIII exhorted Catholics to support, in principle, universal emancipation – an exhortation we are bound to accept – he did not articulate “a formal, absolute and universal condemnation of slavery” in the cited encyclical
• The assertions that the Church lacked “moral criteria that matured over time” failed to condemn an intrinsically evil institution, and that due to a lack of “mature moral criteria,” “political” and “economic” factors “overcame the demands of the Gospel,” are gravely deleterious to the indefectibility and holiness of the Church – as well as undermining of Leo XIV’s own doctrine.

Slavery in the Roman Empire

The Church was born into the Roman Empire. As with the rest of the world, slavery was endemic in the Empire, and slaves formed well over half of the population of Rome.

Father Edward Cahill describes the condition of these slaves:

(They) were practically deprived in law of all human rights and belonged, like chattels or cattle, to their masters. The slaves working in the fields usually had chains on their feet. Their food consisted of bread, water and salt. At night they were kept in damp underground cells with little or no ventilation. The old or weak were commonly allowed to perish like worthless cattle. If it occurred that a Roman citizen was killed in his own home, all the slaves were, or by a provision of the law might be, executed without enquiry or trial.

How was this possible? He explains further:

The pagans of ancient Greece and Rome, whose teachings have partially reappeared in the non-Christian philosophy and jurisprudence of our own days, measured a man’s dignity and rights principally or solely by the amount of material goods he controlled. The man himself, despoiled of his belongings, was little better than nothing.

Hence the slave was regarded as a mere chattel, devoid of personal rights, and meant essentially for his master’s good. Even the freeman, if poor, was treated with supreme contempt, and, in practice, reduced almost to a state of servility. Infanticide and abortion were freely practised, and were formally recommended even by such philosophers as Plato and Aristotle, in the interests, as they understood it, of the public good.

Far from being subject to a “doctrinal development,” the Church has long understood that the institution of slavery is not how men should be living, and, in a qualified sense, an evil which should end. For these reasons, she a) condemned the abuses and worked for better conditions for slaves; b) advocated strongly for the liberation of slaves; and c) built a society upon her own principles, in which slavery was no longer necessary.

Fr. Cahill also writes:

The abolition of slavery was perhaps the greatest and most decisive triumph of Christianity in the social life of the people. That the disappearance of slavery among the European nations was a result of Christian principles is recognised by all historians.

To understand how and why the Church proceeded in the way she did, let us consider the way in which civil authorities treated slavery in the modern era.

The slave trade was abolished in the British Empire in 1807, and the institution of slavery itself was abolished in most of its colonies in 1833. But although slavery existed in British colonies, it was not (legally) practiced in England and so the institution did not play anything like the role it did in parts of the United States and its economy. In the United States, slavery was definitively abolished with the 13th amendment of 1865 after Lincoln’s 1863 Emancipation Proclamation (although even after 1865, the United States retained the right to impose “involuntary servitude” as a punishment for crime). These measures led to the immediate emancipation of around four million African American slaves.

In the Roman Empire, the Church took a different approach to the modern abolitionist movement. Fr. Cahill explains why the universal emancipation of the enormous numbers of slaves in the Roman Empire was considered impossible:

The slave question was the most troublesome and thorny of all the difficulties that the Church had to deal with. To liberate the slaves at once, even if it were possible, would mean a social upheaval the result of which no one could foresee; and would have been fatal even to the interests of the slaves themselves. The numbers of slaves were immense, and the institution of slavery was deeply rooted in the manners, the ideas, and the whole social life of the people. Hence the Church had to proceed slowly and cautiously.

In the face of this, the Church proceeded in the following ways:

• Preaching the equality of all in natural dignity, responsibility, and eternal destiny
• Breaking down the contempt with which slaves were viewed by masters and free men
• Endowing the slaves with a “moral regeneration,” a sense of personal responsibility, and the possibility of supernatural perfection
• Rejecting the idea that manual work is degrading, and insisting on the necessity of some form of labor (whether servile or otherwise) for all
• Insisting on the duties of masters toward their slaves as a corollary to the obedience with which they were owed, and punishing abusive masters
• Administering the same sacraments to all men regardless of condition
• Ordaining clerics and even electing popes of servile origin
• Burying deceased slaves and freemen together without distinction
• Taking command of the custom of manumission (the liberation of slaves) as a rite that took place in churches
• Encouraging the example of Christian masters who liberated their entire

“Besides all this,” Cahill concludes, “the general attitude of the Christians towards their slaves and towards the poor set an example which profoundly affected the whole tone of Roman Society.”

Christianity proclaimed that all men – the Emperor, the slaves, and everyone in between – were of the same nature, endowed with the same dignity, and bound by the same law of God. Regardless of their condition, all were redeemed by the precious blood of Christ, and called to the same eternal destiny in Heaven.

The early Christians adopted and lived this teaching. They increasingly regarded the slaves as their equals in human dignity and responsibility. The slaves were embraced by the Church, and Roman Christian slave owners were taught (and accepted) that the slaves were even a part of their families in which all were “united by close ties of charity and piety.”

As an example of the results of this Christian influence, groups of slaves on Roman estates gained privileges and rights, and their status became “far superior to anything that could be properly termed slavery.” When Christianity began to take root, the Theodosian Code withdrew the right of life and death held by masters over slaves (as well as fathers over children). The same Code gave slaves the right to acquire property, and other protections against abuses by tyrannical masters. Many Christian masters emancipated the slaves and were praised for doing so.

The fall of the Western Empire

During the periods of conflict, migration, invasion and evangelization that followed the fall of the Western Empire, the Church and her officers took the part of slaves, offering them protection against wrongs and insisting on their rights. Cahill again writes:

As the nations became Christian, the Church again intervened in their behalf. It procured the liberation of large numbers of slaves in every country. Documents of the 5th, 6th, and 7th centuries contain numerous records of captives who had been reduced to slavery being redeemed by bishops, priests, monks and pious laymen. Such redeemed captives were sometimes sent back in thousands to their own country.

During all these centuries, enactments were constantly made in the national and provincial Councils of the Church in the interests of the slaves, providing for the protection of maltreated slaves and for the help and patronage of those that were liberated, securing the validity of the marriages of slaves, enforcing in their interests rest on Sundays and feast days, forbidding or limiting traffic in slaves and for4bidding that freemen be reduced to slavery.

Magnifica Humanitas mentions that “(i)n antiquity and the Middle Ages many individuals and even ecclesiastical institutions had slaves.” We have already discussed the Church’s attitude to slaves in antiquity; but with regard to the Middle Ages, the encyclical fails to mention that the treatment of slaves on ecclesiastical estates was so different from pagan slavery that it was given a different name. This treatment not only led to the disappearance of slavery itself, but also the controlled elevation of the slave class to a status considerably better, in many respects, than the working classes of our day.

Cahill explains:

In the early centuries of this period the Church, owing to several causes, found itself in the possession of immense estates in every country of Europe.

The slaves in question were attached to these estates by law, and they could not be removed from them. This meant, however, that they enjoyed fixed work and permanent homes – unlike many free men. The Church began improving their position, and her influence meant that even the slaves on “secular” estates progressively gained the same privileges and protections. This was, essentially, the transformation of slavery into serfdom – a middle position between slavery and freedom – by the tenth century. Serfdom in turn was progressively transformed by the Church into “peasant proprietorship”, with the great range of freedoms this entailed. In the meantime, Cahill states that the condition of serfs “was very much better than the conditions of large sections of the poorer classes in present-day Europe and America” – even while the Church continued to work for complete emancipation. As a result, he says, “slaves were comparatively few even in the 11th century, and slavery had practically disappeared before the opening of the 13th.”

While the Church sought to bring about the end of slavery in the most peaceful and fruitful way possible, the slave trade continued unabated in the Islamic world – and without the strict protections required by the Church. As a result, whole religious orders were established for the specific goal of redeeming slaves taken by non-Christian forces. These orders include the Mercedarians and the Trinitarians, both founded by canonized saints. Members of these orders would even sometimes exchange places with the slaves in order to secure their liberation. (In later years, men such as St. Peter Claver would minister to the African slaves, bringing them comfort both on the slave ships and the plantations.)

The condition of serfdom

In the Middle Ages, the serf generally held a sizable holding of land, which he tilled for himself while paying a tax and certain tributes to the lord. He had the right to pass on his holding to his heir, with the lord having certain claims prior to the succession. The serf was obliged to carry out paid work on the lord’s land for a few days of the week, with the rest of the time being at his own disposal – whether for tilling his own land, or pursuing artisanal crafts, and so on.

None of these rights could be changed by the lord at will. The serf was protected against eviction, transference, and even the removal of his land when in debt. He came to be the true master of his property and holdings and enjoyed many rights over the communal lands (including fishing rights and grazing rights) – until at last, under the influence of the Church, many of the limitations on the serf passed away whilst the customary liberties and protections remained.

Cahill summarizes this development as follows:

The history of slavery and serfdom, and the gradual process of emancipation, which took place under Christian guidance, point unmistakably to the conclusion that the influence of the Catholic Church in every country tends strongly towards the freedom and well-being of the weaker members of the community. When that influence is withdrawn, the general trend of development inclines in the opposite direction.

But to understand the situation of slavery in recent centuries, we must consider the nature of slavery itself.

What is slavery?

In 1866, the Holy Office defined slavery in the following terms:

(T)hat sort of ownership which a slaveowner has over a slave is understood as nothing other than the perpetual right of disposing of the work of a slave for one’s own benefit – services which it is right for one human being to provide for another.

The terms of this definition must be understood. Traditional Catholic doctrine understands slavery as the institution by which one man, by a limited set of legitimate titles, gains “a perpetual and universal right over all the works of his servant,” and in which he is obliged to “take care of the servant, and diligently perform for him all the duties of humanity.” St. Thomas Aquinas notes:

A slave is his master’s chattel in matters superadded to nature (viz. his work and the fruits of his work), but in natural things (viz. the right to eat, sleep, marry or pay the marital debt, etc.) all are equal.

For these reasons, St. Thomas also states that a slave, equal to his master and all men according to nature, was entitled to marry without the master’s knowledge or consent; that he should not be transported to a foreign country away from his spouse, and that he was bound to obey his master only in that which could be lawfully and morally commanded.

The Church traditionally held that the institution of slavery – in the narrow and specific sense mentioned above – though a result of the Fall and Original Sin, is not in itself contrary to natural or divine law. St. Thomas Aquinas teaches that, in the state of innocence, men would have been subject to each other only in respect to their own good (e.g., education), or to the common good of society. The subjection of one man to another’s private good (as in the institution of slavery) would not have occurred without the Fall.

Philosophers and theologians held that liberty was nature’s “first intention” for men, but that its “second intention,” within the fallen order, tolerated an institution of subjugation according to a limited set of “just titles.” To repeat and summarize, the traditional Catholic teaching held that slavery is neither commanded by the natural law nor condemned by it – but was something that should be rendered obsolete.

This is why the same Holy Office ruling states:

Although the Roman Pontiffs have left nothing unattempted whereby they might abolish slavery everywhere among the nations, and although it ought to be credited to them chiefly that already for several centuries no slaves are held among very many Christian peoples ; nevertheless slavery itself, considered in itself and absolutely, is by no means repugnant to the natural and divine law, and there can exist several just titles of slavery, such as may be seen in the approved theologians and interpreters of the sacred canons.

The “just titles” commonly recognized as legitimate included a) being captured in war or hostilities, b) punishment for certain crimes, c) debt, d) birth in a condition of slavery, and e) voluntary acceptance. Outside of such “just titles,” the enslavement of innocents was condemned by the Church.

For example, it was not legitimate to subjugate peoples based on their race or on an alleged inferiority of their race. No racial or “supremacist” titles were recognized as a legitimate basis for the subjugation of peoples.

This is why the Mosaic Law included forms of slavery and why St. Paul both returned the fugitive slave Onesimus to his master (Philemon) and enjoined slaves and masters to exercise the Christian virtues of justice and charity toward each other (as human persons of the same nature, dignity and destiny). None of this would have been possible if all forms of slavery were evil in themselves.

This is also why there were several Papal grants authorizing the enslavement of the “Saracens” (i.e., Muslims) with whom Christendom had been at war for a long period. At times, these permissions were taken by civil powers as a carte blanche to enslave non-Christians (e.g., in the New World) – especially when these peoples customarily enslaved each other ; these lax interpretations were subject to repeated condemnation by the Church, as we shall see below. Both ecclesiastical and civil powers took steps to condemn the unjust subjugation of indigenous peoples and to ensure the liberation of those enslaved in this way. Even Fr. John Francis Maxwell, a critic of the Church’s traditional teaching, recounts the various condemnations issued by the Church, Popes and churchmen in this period:

• In 1537, Pope Paul III (in Sublimis Deus) approved a Spanish Royal Edict which forbade reducing Indians to slavery and issued a Bull which affirmed the humanity and rights of American Indians, and nullified any enslavement of non-hostile Indians that had taken place
• In 1591, Pope Gregory XIV (in Cum sicuti) ordered, on pain of excommunication, the liberation of all Indian slaves in the Philippines held by Spaniards
• In 1639, Pope Urban VIII (in Commissum Nobis) forbade, on pain of excommunication, the subjugation of the indigenous peoples of Paraguay, Brazil and elsewhere “on any pretext or right whatsoever, as well as all slave-trading in Indians.”
• In 1741, Pope Benedict XIV issued a Brief (Immensa Pastorum) to the bishops of Brazil and Portuguese dominions, condemning the unjust subjugation of Indians regardless of their religion, as well as abusive treatment of these

He also renewed and confirmed the acts of Popes Paul III and Urban VIII.

When the plight of African slaves (who, in many cases had been subjugated and sold by their fellow Africans) became common knowledge, the transatlantic slave trade attracted similar Papal condemnations.

• In 1686, the Holy Office commanded Catholic traders to carefully discriminate between those who had been subjugated under a legitimate title, and those who had been unjustly enslaved. Its decree commanded traders to emancipate all slaves who had been unjustly subjugated and to make compensation for their injuries, and to inquire into any cases of a doubtful title
• In 1839, Pope Gregory XVI (in In Supremo Apostolatus) condemned the African slave trade as “unchristian and morally unlawful” – whilst also referring to the Scriptural teaching on the duties of slaves and masters, and the great good of emancipation. He forbade the unjust subjugation of peoples, as well as slaves being treated as animals and subjected to the hardest work.
• In 1861, Pope Pius IX knighted Augustin Cochin, the former Mayor of Paris, for his book on the abolition of slavery
• In 1864, Bishop Augustine Verot of Florida, while recognizing the legitimacy of slavery in principle, called for Catholics of the Confederate States “to ameliorate the existing legal system of chattel-slavery and divest it of the features which would make it odious to God and man.”
• In 1866, as we have already seen, an answer from the Holy Office renewed some of the provisions of the 1686 decree, and condemned abusive treatment even of slaves considered as justly subjugated. It also reaffirmed the desire of the Roman Pontiffs to see the institution abolished, and described the Atlantic slave trade as “that most iniquitous traffic which is reprobated and strictly forbidden by the Apostolic constitutions of the Roman Pontiffs.

This latter decree also taught that the slave owner’s right over a slave “is understood as nothing other than the perpetual right of disposing of the work of a slave for one’s own benefit” and clarified that this was limited to “services which it is right for one human being to provide for another” (viz., nothing immoral or degrading). It also set out the duties of the master, including that he “should do nothing which might endanger the life, virtue or Catholic faith of the slave,” and should not separate married slaves.

In light of these examples, we are now equipped to consider Pope Leo XIII’s interventions and evaluate whether – as Magnifica Humanitas alleges – they represent a break with the Church’s prior teaching and praxis.

While Pope Leo XIII exhorted Catholics to support, in principle, universal emancipation, he did not articulate “a formal, absolute and universal condemnation of slavery” in the cited encyclical

Magnifica Humanitas states:

In continuity with the tradition inaugurated by Leo XIII, the Church renews her firm condemnation of all forms of slavery, trafficking and the commodification of persons. (n. 174)

It was only in the nineteenth century that a formal, absolute and universal condemnation of slavery was clearly articulated, notably under Pope Leo XIII. (n. 176)

The cited document is Pope Leo XIII’s 1888 encyclical In Plurimis, which is misrepresented by Magnifica Humanitas.

While Pope Leo XIII praises the government of Brazil’s liberation of large numbers of slaves, strongly criticizes the institution of slavery, and expresses a wish (to which Catholics are obliged to conform) to see it eradicated from the world, he by no means issues a “formal, absolute and universal condemnation of slavery.” On the contrary, his overview of the Church’s history with regard to slavery makes clear his acceptance that some forms of slavery have been legitimate, even if it be pressing to see them ended.

For instance, he praises the Fathers of the Church for their treatment of the issue, specifically mentioning that “the rights of masters extended lawfully indeed over the works of their slaves” (viz. that which is “superadded to nature,” as St. Thomas put it):

(T)he holy Fathers made a wise and admirable exposition of the apostolic precepts concerning the fraternal unanimity which should exist between Christians, and with a like charity extended it to the advantage of slaves, striving to point out that the rights of masters extended lawfully indeed over the works of their slaves, but that their power did not extend to using horrible cruelties against their persons. (n. 10. Emphasis added)

He cites St. John Chrysostom, who himself sharply distinguished between the degraded and immoral slavery of the Roman empire and that which could be legitimate:

St. Chrysostom stands pre-eminent among the Greeks, who often treats of this subject, and affirms with exulting mind and tongue that slavery, in the old meaning of the word, had at that time disappeared through the beneficence of the Christian faith, so that it both seemed, and was, a word without any meaning among the disciples of the Lord. (Ibid. Emphasis added)

Summarizing Chrysostom’s argument, he includes the following:

(I)n order that that kind of evangelical brotherhood may have more fruit, it is necessary that in the actions of our ordinary life there should appear a willing interchange of kindnesses and good offices, so that slaves should be esteemed of nearly equal account with the rest of our household and friends, and that the master of the house should supply them, not only with what is necessary for their life and food, but also all necessary safeguards of religious training. (Ibid. Emphasis added.)

He encouraged the Brazilian bishops to continue working for the full liberation of all who are enslaved, but in terms that would be impossible when discussing something intrinsically immoral (such as abortion):

Through your means let it be brought to pass that masters and slaves may mutually agree with the highest goodwill and best good faith, nor let there be any transgression of clemency or justice, but, whatever things have to be carried out, let all be done lawfully, temperately, and in a Christian manner.

It is, however, chiefly to be wished that this may be prosperously accomplished, which all desire, that slavery may be banished and blotted out without any injury to divine or human rights, with no political agitation, and so with the solid benefit of the slaves themselves, for whose sake it is undertaken. (n. 21)

That which is intrinsically evil – such as abortion, or the human sacrifice of the Aztecs – cannot be subject to concerns about “political agitation” or the “human rights” of those responsible. It must simply and immediately end.

The fact that Pope Leo XIII treats the issue in these ways demonstrates that Magnifica Humanitas is incorrect to state that there was a “delay” in an absolute condemnation of slavery until the 19th century. This is because a) such a condemnation did not occur, and indeed could not have occurred – because it would be impossible for the Church to condemn slavery absolutely; and b) because Pope Leo XIII’s intervention in 1888 was not a change or novelty but rather in continuity with the previous centuries of the Church’s teaching and praxis.

The Church, even while tolerating the existence of slavery within certain bounds, had always considered it to be something that should be removed from society. Thus, while Pope Leo XIII left untouched the legitimacy of slavery in the speculative order, he exhorted all Catholics to favor universal emancipation of all slaves.

In accordance with the constant teaching of the Church, as expressed by Pope Pius XII in Humani Generis, Catholics are strictly obliged to accept a papal exhortation such as this, offering it a “religious assent” of the intellect and will.

Conclusion

Magnifica Humanitas errs in implying that the Catholic Church has anything for which to apologize with regard to the issue of slavery.

From the beginning, the Church proclaimed that slavery, while not contrary to divine or natural law, was far from the ideal way in which human persons should live. She condemned abuses, evil forms of slavery and unjust enslavement. She elevated slaves, humanized their masters, and brought about conditions in which slaves could be dignified, emancipated, and the institution ultimately rendered unnecessary. She ultimately pointed all of society to the highest good – God himself – and the eternal salvation of men, whatever their condition.

Even the Protestant historian and politician, Thomas Babington Macaulay – himself the son of an abolitionist – wrote the following of the Church’s role in transforming the slave class into a free landowning peasantry:

Moral causes noiselessly effaced first the distinction between Norman and Saxon, and then the distinction between master and slave. It would be unjust not to acknowledge that the chief agent in these two great deliverances, the greatest and most salutary social revolutions that have taken place in England, was religion … The benevolent spirit of the Christian morality is undoubtedly averse to distinctions of caste. But to the Church of Rome such distinctions are peculiarly odious.

By contrast, where the influence of the Church was limited, conditions worsened. Under the rise of Protestantism, the progressive improvement for serfs in Germany, Denmark and Sweden was reversed. Similarly, the condition of serfs in Orthodox Russia deteriorated over the centuries, with serfs losing their rights to permanent homes and not to be sold to other owners.

As the Church’s influence further declined, the condition of free men similarly deteriorated, particularly in the Industrial Revolutions. While it is true that the absolutist abolitionist groups around this time emerged from Protestant backgrounds, it is also true that the general condition of the working classes in Protestant countries (and countries where the Church had lost influence) had become so akin to slavery itself that the Popes were compelled to promulgate encyclicals such as Rerum Novarum and Quadragesimo Anno to address the situation.

In short, Christendom and the Catholic social order offered the best conditions for all men, and the most stable and effective way for the institution of slavery to end. It is therefore false for Magnifica Humanitas to claim that the Church lacked the “moral criteria that matured over time.” It is similarly false for the encyclical to claim that:

Political and, at times, even economic needs overcame the demands of the Gospel. The need for evangelization was frequently compromised or at least misunderstood with regard to the needs of worldly powers, thus relativizing the problematic incompatibility of slavery with the Christian conscience. (fn. 174)

The Church, as such, cannot be guilty of putting political, economic or worldly considerations above Catholic truth. It is also an implicit denial of the Church’s property of holiness, which makes it impossible that her traditional doctrine can be opposed to faith or morals. This is not to deny that individual Catholics, including members of the clergy, may have sinned grievously in relation to slavery – but none of this engages the Church herself.

Further, a comment such as this – and the claim that the Church previously lacked the “moral criteria that matured over time” – is an implicit denial of the Church’s infallibility and indefectibility. It cannot help but undermine all magisterial teaching, and the very concept of a divinely appointed teaching authority. It makes it impossible to assent to the Church’s teaching at any time, given the possibility of future maturation of moral criteria. All such assent becomes provisional rather than certain.

On this basis, critics could allege that Leo XIV himself – in his stated positions on the environment, LGBT issues, and even on the current issue of slavery – is overcome by political and economic needs and by a desire to placate worldly powers. There is no basis for claiming that the “moral criteria” that he employs will not mature further in the future until it arrives at the idea that that slavery is legitimate or even desirable – and in a more degraded form than even that of Pagan Rome.

However, the creation of doctrinal instability and uncertainty, and the suggestion that doctrines of faith and morals can be updated at future points in accordance with the needs and attitudes of humanity, is indeed the very purpose of the synodal ideology and the heresy of modernism, as has been shown on many occasions.