Why the "Slavery Argument" Fails to Sway Catholic Teaching on Homosexuality"

Addressing a historical myth propping up a bad argument for progressive Christianity

A common argument against orthodox Catholicism is that the Catholic Church "changed its position" on the topic of slavery so therefore it's only prejudice that keeps it from also changing its position on the topic of homosexuality in light of our new, enlightened perspective of what it means to be gay informed by modern science and secular, liberal ethics.

But this is incredibly misleading.

Grok easily debunks this argument:

"The Catholic Church’s response to the perception that it "changed its position" on slavery, and the reconciliation of this with the concept of infallibility, hinges on a careful distinction between the Church’s authoritative, infallible teachings and the historical practices or failures of individual Catholics, as well as a nuanced understanding of how doctrine develops over time.

Did the Church Change Its Position on Slavery?

The narrative that the Catholic Church only recently condemned slavery or reversed an earlier endorsement oversimplifies a complex history. The Church has consistently opposed unjust forms of servitude—such as chattel slavery based on race or economic exploitation—since its early days, rooted in the belief that all humans are made in God’s image (Genesis 1:27) and share equal dignity. Historical evidence shows papal condemnations of unjust slavery as early as 1435, when Pope Eugene IV, in Sicut Dudum, demanded the liberation of enslaved Canary Islanders under penalty of excommunication. Later, in 1537, Pope Paul III’s Sublimis Deus declared that indigenous peoples of the Americas could not be enslaved, denouncing such acts as satanic. These pronouncements were reinforced by subsequent popes, like Gregory XVI in 1839 (In Supremo Apostolatus), who condemned the transatlantic slave trade as an affront to human dignity.

However, the Church did not always outright reject all forms of servitude. Historically, it tolerated "just title" servitude—such as penal labor or voluntary indenture—common in ancient and medieval societies, provided slaves were treated humanely and their spiritual equality was recognized. This distinction is key: the Church condemned slavery as an intrinsic evil when it violated natural law and human dignity, but it did not immediately demand the abolition of all servitude in societies where it was deeply entrenched, often due to practical limitations rather than doctrinal approval.

Critics point to instances where Catholics, including clergy and religious orders like the Jesuits, owned slaves, or where popes like Nicholas V (in Dum Diversas, 1452) appeared to authorize enslavement of non-Christians during wartime. These actions reflect historical context—war captives were often enslaved under then-accepted norms—and the failures of individuals or local churches, not a formal, infallible endorsement of chattel slavery. The Magisterium (the Church’s teaching authority) never declared slavery intrinsically good or morally obligatory; rather, its stance evolved from tolerating certain forms to explicitly condemning all involuntary servitude as incompatible with Christian anthropology, culminating in Vatican II’s Gaudium et Spes (1965), which lists slavery among "infamies" that dishonor the Creator.

Reconciling with Infallibility

Catholic teaching on infallibility applies only to matters of faith and morals definitively proclaimed by the pope or an ecumenical council for the universal Church. It does not mean every papal statement, historical practice, or cultural accommodation is infallible. The Church distinguishes between:

• Immutable Doctrine: Core truths (e.g., the Trinity, human dignity) that cannot change.

• Development of Doctrine: The application of these truths can deepen over time as the Church reflects on their implications in new contexts, a concept articulated by St. John Henry Newman. For example, the inherent dignity of all persons was always taught, but its full implications for slavery became clearer as societal and theological understanding progressed.

• Disciplinary or Prudential Judgments: These, like tolerating servitude in certain eras, are not infallible and can shift as circumstances change.

The Church’s evolving stance on slavery is thus seen as a development, not a contradiction. It never infallibly taught that chattel slavery was morally permissible; instead, its earlier silence or tolerance in some contexts reflected pastoral pragmatism—working within sinful structures to mitigate harm—rather than doctrinal approval. When popes like Leo XIII in 1888 (In Plurimis) explicitly condemned slavery in all forms, it built on prior teachings, clarifying that no form of involuntary servitude aligns with the Gospel.

Catholic Response Today

Modern Catholic apologists, such as Paul Kengor in The Worst of Indignities, argue that the Church was ahead of secular society in condemning unjust slavery, citing papal bulls and the witness of saints like Peter Claver, who ministered to slaves. They acknowledge the scandal of Catholics who defied these teachings—e.g., Jesuit slaveholding in the U.S.—but emphasize that such actions were sins against the Church’s own principles, not evidence of a doctrinal flip-flop. The Church today sees its history with slavery as a call to repentance and reconciliation, as seen in efforts like the Jesuits’ recent initiatives to make amends to descendants of those they enslaved.

In short, the Church reconciles its infallibility with this history by asserting that its core teaching on human dignity never changed; rather, its application sharpened over time. The failures of Catholics to live this out do not negate the truth of the doctrine but underscore the need for ongoing conversion—a point Pope Francis has echoed in rejecting slavery as a sin against God’s image in humanity."

Conclusion

As Grok shows, it’s misleading to suggest that the Church “changed its mind” on the topic of slavery and that this is somehow proof that Church teaching ought to be “updated” in light of the modern development of secular ethics and new cultural paradigms regarding liberal, permissive attitudes about sex.

The Church teaching on homosexuality is not grounded in a prejudicial attitude against homosexual persons per se because the same theological argument also provides a moral obligation for heterosexual persons to abstain from masturbation, sex outside of marriage, watching pornography, or remarriage after divorce, practices that are all considered normal and perfectly morally innocuous within mainstream secular culture in the West, and all of which would provide a difficult “narrow road” for heterosexuals to follow if they wanted to be in alignment with God’s commandments.

Is the Church “heterophobic” because it tells heterosexual men it’s intrinsically disordered to do what comes very natural to them, which is masturbation, despite it feeling both good and natural and “hurts no one”? No, that’s ridiculous.

The Church is not “anti-gay.” It is pro-Natural Law, which is derived from God’s Eternal Law and His Divine Blueprint of Creation for human beings to be naturally sexually complementary as male and female for purposes of procreation and the unitive “fitting together” of the opposite pair of genitalia into one flesh. Indeed, Jesus Himself endorses this Divine Blueprint of what marriage is all about, referring back to the theological Blueprint of Creation found in Genesis, which defines, ultimately, what our sexual organs and sexual appetites are properly ordered towards in accordance with His Eternal Law:

19 When Jesus had finished saying these things, he left Galilee and went into the region of Judea to the other side of the Jordan. ² Large crowds followed him, and he healed them there.

³ Some Pharisees came to him to test him. They asked, “Is it lawful for a man to divorce his wife for any and every reason?”

⁴ “Haven’t you read,” he replied, “that at the beginning the Creator ‘made them male and female,’^{[a] 5} and said, ‘For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh’^[b]? ⁶ So they are no longer two, but one flesh. Therefore what God has joined together, let no one separate.” (Matthew 19)

In the Catholic Catechism 2359, the Church teaches:

"Homosexual persons are called to chastity. By the virtues of self-mastery that teach them inner freedom, at times by the support of disinterested friendship, by prayer and sacramental grace, they can and should gradually and resolutely approach Christian perfection."

By the same token, heterosexuals who, through no choice of their own, are incapable of finding a suitable marital partner, are also called to live a life of chastity by not having premarital sex or masturbating.

As evangelical writer Christopher Yuan says in the book of the same title, both homosexuals and heterosexuals are called to live a life of Holy Sexuality in accordance with the Natural Law derived from God’s Eternal Blueprint for marriage, which is grounded in the ontological reality of Male and Female coming together in a unitive way, aligned with openness towards the possibility of bringing forth new life into the world.

That is not “homophobic” teaching born out of a fear or prejudicial attitude against homosexuals. It defines a narrow road of righteous living for both homosexuals and heterosexuals alike while also framing this call for sexual holiness within the paradigm of Grace, Mercy, and Love through the Redemptive power of the Lord Jesus Christ, who died so that all sins might be forgiven, regardless of whether those sexual sins are committed by heterosexuals or homosexuals.

It is a hard path for everyone, gay or straight, to follow God’s Blueprint for Holy Sexuality but many gay Christians have found a higher purpose and Joy in Christ in following God’s Will, which is Eternal and transcendent of the modern liberal secular ethics where anything goes and Christian orthodoxy is rejected if it does not fit into modern cultural whims and preferences.

Above all, the Catholic Church still affirms the intrinsic dignity of homosexuals as being made in the Image of God and worthy of respect, compassion, and kindness:

CCC Paragraph 2358 states:

"The number of men and women who have deep-seated homosexual tendencies is not negligible. This inclination, which is objectively disordered, constitutes for most of them a trial. They must be accepted with respect, compassion, and sensitivity. Every sign of unjust discrimination in their regard should be avoided. These persons are called to fulfill God’s will in their lives and, if they are Christians, to unite to the sacrifice of the Lord’s Cross the difficulties they may encounter from their condition."