LGBTQ advocates urge the Catholic Church to recognize same-sex relationships as morally licit. Same-sex couples, they argue, are loving and benign and can live in peaceful coexistence alongside heterosexual couples in the Church.
But what exactly are these advocates asking the Church to accept? What would happen, as a matter of logic and practical consequence, if the Church heeded their cry?
Imagine, for argument's sake, that the Church were to change its teaching on homosexual activity. What would that mean? I can count a dozen major things that would happen as a result of such a monumental shift.
First, the Church would have to explain why Her consistent and universal teaching over 2,000 years — that to be licit, every conjugal act must be open to life —was wrong (see, e.g., Gaudium et Spes, §48: "By their very nature, the institution of matrimony itself and conjugal love are ordained for the procreation and education of children and find in them their ultimate crown").
The Church has never reversed course like that before. And confused arguments about the Church's alleged change in doctrine on slavery or the death penalty are toothless, as Paul Kengor, Ed Feser and others have shown.
Second, the Church would have to explain why the repeated condemnations of homosexual acts in the Old Testament and the Pauline epistles are wrong (see Genesis 19:1–38; Leviticus 18:22; Leviticus 20:13; Romans 1:26–27; 1 Corinthians 6:9–10; 1 Timothy 1:8–10 and Jude 1:7).
Third, the Church would have to explain how Christ's teachings on sexuality — including His teaching that marriage is an indissoluble one-flesh union of a man and woman — are compatible with same-sex ideology.
As Paul Gondreau has explained, "If Jesus opposed divorce on the grounds that, as He says, 'From the beginning of creation, God made them male and female' (Mark 10:6), it would have been exceedingly incongruous, to say the least, if He should not also have opposed homoerotic relationships on the same grounds; namely, that they violate the male–female structure (dimorphic complementarity) of our sexuality" (from Thomas Aquinas, Biblical Theologian).
Fourth, the Church would have to explain why Scripture's supposed errancy on this fundamental moral issue does not undermine the inerrancy of Scripture on all moral matters.
Fifth, the Church would no longer have any principled ground to object to the sin of fornication. The Catechism of the Catholic Church decries fornication as "gravely contrary to the dignity of persons and of human sexuality, which is naturally ordered to the good of spouses and the generation and education of children" (¶2353). If homosexual acts are licit, then the generation and education of children are irrelevant (or at least incidental) to sex. If sex has no essential relationship to children, then why should the Church reserve it only for the married? Sex can create bonds of intimacy among the unmarried, too — that is the ethos of the sexual revolution.
Sixth, having blessed non-procreative sexual acts, the Church could no longer prohibit the use of contraceptives. The Church could condemn some contraceptives (such as the birth control pill) as abortifacients, but not as contraceptives.
Seventh, the Church would likely have to change Her doctrine on "assisted reproductive technologies." In order to have a child who is biologically related to one of the "spouses," the same-sex couple must resort to ART, either via surrogacy or in vitro fertilization, or both. If the demands of divorced-and-remarried Catholics seek to force the Church to compromise on Jesus' teachings about the indissolubility of marriage, then the demands of same-sex couples will likely force the Church to compromise on Her natural law teaching on the evils of ART. If sex is incidental to reproduction, then reproduction is incidental to sex.
Eighth, the Church would also have to change Her teachings on the family. From the black letter of the Fourth Commandment ("honor your father and your mother") to the salient text of the Catechism ("a man and a woman united in marriage, together with their children, form a family" (¶2202), the Church has always grounded Her teachings on the family in the complementarity of the sexes. Using the titles "mother" and "father" will instead give way to using generic, gender-neutral terms like "parents" or "caregivers."
Ninth, the Church will have to refashion Her teachings against the evils of polygamy and polyandry. The Church could still argue against these practices on the grounds of jealousy and exclusivity, as gay activist Jonathan Rauch argued decades ago. But the central premise of the LGBTQ movement, that the only moral norm a person needs is his subjective sexual desires, supports polygamy and polyandry. If three adults feel deeply that only a "throuple" will meet their needs, then who is the Church to stand in their way?
Tenth, the Church will face intense pressure to modify Her understanding of Jesus as the "Bridegroom" and the Church as the "Bride of Christ." Scripture repeatedly speaks of Jesus and the Church in these terms (see John 3:29; Matthew 9:14–15; Mark 2:18–20; Luke 5:33–35; Revelation 19:7, 21:2, 22:17; 2 Corinthians 11:2; Ephesians 5:25–27). And the Church has a long tradition of reading the Song of Songs as a prolonged metaphor for the relationship of the Church (the Bride in waiting) longing for Christ, Her Bridegroom. The Church would have to supplement or replace that "heteronormative" and "binary" language with more inclusive language, including homoerotic imagery.
Eleventh, the Church would have to decide whether transgender "men" (biological women) are eligible for the priesthood and male religious orders. If they are eligible, then the Church will have to explain how that innovation does not conflict with Her universal and consistent teaching. If they are not eligible, the Church will have to explain why Her praxis does not undermine the central tenet of the LGBTQ movement — that a person's identity is defined by his subjective sexual desires.
Twelfth, and most critically, the Church would have to explain why anyone should listen to Her about anything. Having denied the clear teachings of Scripture, Christ, the saints, the Church Fathers and councils throughout history, the Church will have lost the ability to speak coherently on moral and spiritual matters.
If the foregoing authorities were wrong about something as basic as sexual morality — perhaps the most important practical issue for society — then why should anyone believe the Church when She invokes them?
In the face of the illusory merit of LGBTQ apologetics, the Church must stand Her ground. The homosexualist agenda opposes central teachings of the Catholic Church. Far from an innocent addition to the edifice of the Church, the LGBTQ agenda could potentially bring down the house.