Vatican’s new doctrinal note “Una Caro” passionately defends exclusive, lifelong monogamy as the heart of Christian marriage against polygamy and polyamory.
On November 25, 2025, the Dicastery for the Doctrine of the Faith, led by Cardinal Víctor Manuel Fernández, released “Una Caro: In Praise of Monogamy,” an unusually long and lyrical 156-paragraph doctrinal note that mounts the most comprehensive theological, philosophical, scriptural, historical, and even poetic case for monogamous marriage ever published by the Holy See.
Far from a mere disciplinary reminder, the text reads like a love letter to the “two of us,” that intimate, exclusive “we” formed when a man and a woman freely choose total mutual belonging. Written against the backdrop of rising polyamory in the West and persistent polygamy in parts of Africa and elsewhere, the document insists that monogamy is not simply the opposite of polygamy; it is something infinitely richer: the created order’s most radiant icon of Trinitarian communion and of Christ’s unique, spousal love for the Church.
At its core is a single conviction: marriage, by its very nature, is ordered to the “one flesh” unity described in Genesis 2:24 and reaffirmed by Jesus (Mk 10:6-9). Everything else — indissolubility, openness to children, mutual sanctification — flows from this prior, foundational property of unity. While Catholic literature has long emphasized indissolubility, the Dicastery notes that the unitive dimension, the beauty of exclusive belonging itself, has been “underdeveloped.” “Una Caro” sets out to correct that imbalance.
The document moves gracefully across centuries. It begins in Scripture: from the solitary Adam who finds in Eve the only “helper fit for him” (Gen 2:18-24), through the searing monogamous symbolism of Hosea’s wounded yet faithful love, the Song of Songs’ ecstatic “my beloved is mine and I am his,” to Christ’s return “to the beginning” and Paul’s “great mystery” of Ephesians 5, where the one-flesh bond of husband and wife reveals Christ’s one-flesh bond with the Church.
Church Fathers like Augustine, John Chrysostom, and Tertullian appear next, praising the “inseparable communion of life” and already warning that dividing the flesh divides the spirit. Medieval giants (Thomas Aquinas, Bonaventure) and modern voices (Dietrich and Alice von Hildebrand, Hans Urs von Balthasar, Karl Rahner, Karol Wojtyła) deepen the insight: true spousal love is a total, reciprocal gift of persons that cannot be fragmented without denying the very dignity of the person.
Papal teaching forms a golden thread. Leo XIII defends the equal dignity of woman against cultures that treated wives as property. Pius XI in Casti Connubii elevates conjugal love to “primacy of nobility.” Vatican II speaks of marriage as “intimate communion of life and love.” John Paul II’s theology of the body and Benedict XVI’s Deus Caritas Est anchor eros within exclusive, definitive self-gift. Francis contributes lived realism: patience, kindness, forgiveness, and the daily decision to re-choose one another even when passion wanes.
Philosophically, the note draws on Kierkegaard’s courage to belong wholly to one person, Lévinas’s face-to-face ethics, and Wojtyła’s personalist principle.
Drawing heavily on the young Karol Wojtyła’s pre-papal writings, Fernández argues that whenever a third person is admitted into the intimate space that belongs by right to one alone, the beloved is inevitably reduced — even if only slightly, even if only in theory — from an end in himself or herself to a means. Polyamory, no matter how consensual or spiritually adorned, necessarily fragments the gift. And a gift that is fragmented ceases, at a metaphysical level, to be a gift of the person.
This is not moralism; it is anthropology. To love a person is to say, without reservation and without asterisk: “There is no substitute for you.” Anything less is already a diminishing.
Even Hindu and Tamil texts are respectfully cited for their ancient witness to mutual fidelity “until death.”
Poets — Neruda, Montale, Eugenio Montale, Octavio Paz, Nazim Hikmet, and Emily Dickinson — are invoked not as decoration but as witnesses: great love, when authentic, always sings in the singular. “No one else, my love, will sleep with my dreams.”
Pablo Neruda driving in circles until the lovers “got home, the two of us.” Eugenio Montale descending millions of stairs arm in arm because “with four eyes we see more.” Nazim Hikmet begging the jailer for five things and the fifth is “your eyes, my beloved Matilda.” Octavio Paz offering sleepless nights and whole skies drunk on mountaintops. Emily Dickinson, severe and tender: “That Love is all there is, is all we know of Love.”
The final chapters offer pastoral gold. Mutual belonging is distinguished from possessive jealousy: the person remains an “end in himself,” inviolable; only God fully possesses the sanctuary of the heart. Conjugal charity is presented as the “greatest form of friendship” (Thomas Aquinas), a school of sanctification where spouses help each other toward heaven. Sexuality, far from being marginalised, is celebrated as the bodily seal of total self-gift when lived within this exclusive, charitable communion.
The note closes with a gentle but firm reminder that every genuine marriage, however imperfect, is called to reflect the unique, jealous love of the God who declares, “I am the Lord your God… you shall have no other gods before me.” Monogamy, in the end, is not a constraint but prophecy: the human creature, made for communion, finds its deepest truth only in the irrevocable gift of self to one other — and, through that one, to the One who is Love.
In an age that increasingly treats relationships as customizable and disposable, “Una Caro” is the Vatican’s most eloquent plea yet for the splendour of the “two of us” who, by the grace of the sacrament, become forever one.
- Raju Hasmukh with files from Vatican.va
Related Images:
