Why does the Church say that "same-sex marriage" is impossible?

Stratford Caldecott


Many Christians, just like the rest of the population, experience homosexual attraction, and a good number have come to define themselves as "gay", even if only by inclination. In both England and the United States matters of sexual preference and expression are regarded increasingly as on a par with any other "right to choose". The social and political pressure to abolish the distinct privileges of the traditional married couple, or to extend them to same-sex couples, has become intense.

In the summer of 2003, the Congregation for the Doctrine of the Faith headed by Cardinal Ratzinger issued a document entitled "Considerations regarding proposals to give legal recognition to unions between homosexual persons". Intended to give direction on the matter to Catholic politicians, it was worded so strongly that some accused it of having been intended to give offence, although it is more likely to have been motivated by frustration at the way earlier official statements on this subject have been consistently ignored or downplayed in parts of the Church. The most notorious sentence was this (the emphasis is mine): "There are absolutely no grounds for considering homosexual unions to be in any way similar or even remotely analogous to God's plan for marriage and family. Marriage is holy, while homosexual acts go against the natural moral law. Homosexual acts 'close the sexual act to the gift of life. They do not proceed from a genuine affective and sexual complementarity. Under no circumstances can they be approved.'"

While it is true that active homosexuals are often extremely promiscuous, many do form long-lasting, even lifelong unions characterized by tender affection and self-giving love. Not all such unions exclude sexual contact outside the union, but some do. Is it really possible to reconcile this fact with the Congregation's flat denial of any analogy or similarity between homosexual unions (at least of this sort) and marriage?

What Catholics Understand by "Marriage"

Before trying to answer this question, I want to set aside another set of issues that I do not intend to cover in detail. It seems clear enough that many people cannot help being attracted by or falling in love with someone of the same sex. Why is this? Did God intend to make them that way? In that case, some would say, it hardly seems fair of him to demand that they renounce their feelings or refuse to act upon them. Or have they been "damaged" by genetic inheritance or upbringing, so that their "normal" feelings are diverted into other channels? I am not qualified to enter into the arguments about the physical or psychological causes of homosexuality. What I am concerned about is the Christian response to it. And it is important to remember that love and friendship are at the very heart of Christianity. What is at issue is not the feelings per se, but the genital expression of those feelings, and whether Christianity can make a consistent and convincing case against one whole category of such expression.

It is, after all, the case that the Church restricts genital expression of sexual feelings in the case of heterosexuals too, and not only of those who are in the single state. A married man or woman may fall uncontrollably in love with someone outside the marriage, and the Church regards adultery as a sin. The same strictures – and the same tolerance of human weakness in those who fall, with the continually-extended offer of reconciliation – should be applied to all types of sexual experience. The difficult thing for homosexuals to understand is not the claim that sexual activity may be sinful under certain circumstances, but that, according to the mainstream interpretation of the Christian tradition, there is no legitimate form of homosexual union, equivalent to marriage, within which sexual expression is permitted.

To make sense of this we must first distinguish the subjective order of feelings from the objective order of actions and structures. At the level of feelings there may indeed be a deep bond between two people of the same sex – particular friendships may even outlast earthly life. But a friendship, however deep and intense, and even if it possesses an erotic quality or dimension, is not the same as a marriage. Feelings obviously have a place in marriage, but as an institution and as a sacrament it does not depend upon them. The Vatican document says that marriage is a particular kind of bond between persons that is only possible on the basis of biological gender.

So what kind of a structure is "marriage"? According to the document, it "exists solely between a man and a woman, who by mutual personal gift, proper and exclusive to themselves, tend toward the communion of their persons. In this way, they mutually perfect each other, in order to cooperate with God in the procreation and upbringing of new human lives." Marriage is therefore a communion between a man and a woman which exists for the sake of procreation. It is then "elevated by Christ to the dignity of a sacrament", becoming "an efficacious sign" of the covenant between Christ and the Church (Eph 5:32).

This way of describing marriage is highly technical. It presupposes a long history of theological discussion, and the broader context of Catholic teaching. The phrase "efficacious sign", for example, refers to the nature of the sacraments as symbolic and ritual enactments that by divine grace "effect" or bring about what they signify. What it boils down to is that the vow of marriage, once consummated, brings into existence a new reality: a unity composed of two people – a whole greater than the sum of its parts. This "ontological" union, once freely entered upon in full consciousness by two baptized Christians (who by virtue of their baptism are each members of Christ's "mystical" body), is so strong that the Catholic tradition regards it as indissoluble except by physical death1.

The Four Elements of Marriage

Let us look more closely, then, at the nature of this "ontological" union of a couple in marriage. There seem to be four essential conditions to bring it about. The first is the intention of the couple to create just such a union, which they express in the words of the marriage vow. The second is that the couple consists of a man and a woman. The third is the fact that each member of the couple is a baptized Christian (not necessarily a Catholic). The fourth is consummation of the marriage through sexual intercourse. How are these conditions inter-related?.

The "giving of the word" in a marriage vow, which is in essence the conscious giving of the self, each to each, is the decisive intentional act that establishes the basis for a marriage. It is this intention that seals the analogy between the human and the divine. In God, too, the Word is given. Marriage is an image both of the Trinity as a communion of equal persons, and of the Church as a union between God and man. This resemblance or analogy that exists between marriage, the hypostatic union in Christ, and the divine Trinity in heaven, "connects" the married couple with God in a particular way, making them a living icon of the Trinity.

However, the image is only complete if the couple is already baptized. Baptism means that Christ actually dwells within a person, through the Holy Spirit. This is a more intense form of presence than that of the universal presence of the Creator within the creature. Before being baptized, God is within me, and I may pray to him there; but after baptism I am also within God. Baptism initiates me (even before I fully realize it) into the mystery of the Incarnation, into the "within" of God, so that the life of God as man is being lived through me; my life is that of the Son. The within of God is the Trinity.

Thus for the married couple who are baptized, marital union becomes part of this living out of the Incarnation, and specifically the union of Christ with his Church (the extension of the Incarnation into communion with others). There may even be an implication that the Church recognizes that without being joined to Christ by baptism, a human being is probably incapable of true self-gift – or, at least, that it should not be expected of him.

Consummation also plays a vital role in sealing the marriage covenant. It completes the act of self-gift which is begun in the words of the marriage vow. The reason for this is that the human person includes a body. The Church rejects the Cartesian anthropology that would make the body a merely extraneous machine-like instrument of the mind, in favour of a view that regards the material world as fundamentally good and the human being as inclusive of both matter and spirit. Thus a union of persons includes a union of bodies.

In sexual intercourse the couple forms a biological unit. The whole is greater than the sum of its parts: literally so in the case of a union that results in the conception of new life. The biological incompleteness of each sex on its own, such that it can only fulfil this aspect of its nature by merging with the other, is another essential basis for the supernatural partnership of marriage, and it is this which specifically excludes marriage between two persons of the same sex ("homogamy"). In the act of procreation, and in no other act, two individuals function as a single principle, because it takes both of them to give rise to a new human life. Their union is more than a felt or imagined union of two consciousnesses, or the apparent merging of two sets of feelings into one shared ecstasy; it is an objective union of two embodied persons in a unity that transcends the couple.

To put this another way, the sacramental union is founded on a potential union, or predisposition to union, that is inscribed in our very biology. Christ appeals to this (archetypal) union of male and female "in the beginning" when he re-institutes indissoluble marriage as a sacrament in Matthew 19:4-9. Of course, an individual man or woman is a person and, as such, a true unity created by God in his image. On this is founded the dignity and immortal destiny of each human being. But there is another kind of whole that can only be constituted by a man and woman together. That union, the particular raison d'être of marriage, is not possible for a same-sex couple, however loving and faithful they may be, simply because it is based on those human differences which derive specifically from procreation.


Catholic marriage forms a coherent package, but arguments alone will not convince everyone to buy the package. The question remains: is this merely an ideal, and what is more an ideal that suits some people not others? Furthermore, could a society that no longer recognizes Christianity (let alone Catholicism) as its spiritual foundation not institute a more inclusive form of legal union that would capture many of the traditional elements of Christian marriage without prejudice to Catholics who wish to "marry" in their own, more specialized, sense of the word?

It is, of course, true that many of the conventional or legal elements that have become associated with Christian, sacramental marriage might be detached from this context and applied to other intimate (and not necessarily sexual) relationships. Why cannot close friends live together, or bequeath property to one another, donate pension benefits to each other, and so forth? The limits to this largely depend on whether we regard sacramental marriage as needing or deserving special legal privileges and advantages.

Why might it? Well, for one thing, the sharing of property and the merging of assets makes most sense between people who are undertaking a union that is intended to be permanent. In a society where marriages often end after a few years, and perhaps acrimoniously, the disentangling of what had been legally merged together becomes a major industry in its own right. The presence of children complicates things further, legally and even more importantly, psychologically.

If it is true, as many have argued, that the mental and spiritual health of a child is best secured within a conventional two-sex relationship, where the child lives within an ambience created by a maternal and a paternal figure cooperating together, this creates another set of reasons against the encouragement (through legal institution) of same-sex "marriages" – namely, the well-being of the children who might be adopted by the couple, whether out of genuine love or merely as a lifestyle accessory.

Increasingly, if same-sex unions are recognized as legitimate forms of marriage suitable for bringing up children, the pressure will be even greater on scientists on to develop technologically-assisted forms of reproduction that would enable such couples to have children of their own, should they desire them. It would be argued that to have a child is the "right" of any couple, and that science ought to make this possible. Children are increasingly regarded – as we have seen in recent years – as commodities to be manufactured on demand. The social and psychological consequences of such developments are uncharted, but hardly unpredictable.


Our social fabric is a delicate ecological system, where any structural changes of the sort being discussed will inevitably have immeasurable and irreversible effects on every level from the personal and psychological to the economic and political. For this reason alone, quite apart from any Christian considerations (and I have not even mentioned the guidance of Scripture, which Christians regard as an authoritative guide to the principles that should govern social life), it would seem wisest for politicians not to give in to the pressure on behalf of same-sex unions, but to find other ways to protect the interests of citizens, whether homosexual or not, and the common good of society.

As for Christians themselves, whatever the arguments against the equal legal recognition of same-sex unions, with or without the option of divorce, it is important to remember two facts. The first is that there is a strong and determined lobby determined to push legislation as far and as fast as possible. The second is that homosexuals are human beings like everyone else, and as deserving of respect and love as the rest of us. The attempt to block the political movement towards sexual liberation of gays should never be linked to the kind of un-Christian attitudes that homosexuals rightly regard as hypocritical.

This is linked to a third fact that has been reiterated in Church teaching, but is not always taken as seriously as it might be. It is not essential to human health to indulge one's sexual preferences or desires, whatever Freud might say. A healthy continence is no contradiction in terms. Even within marriage it is essential to attain a level of self-control and purity that makes long periods of abstinence possible. In this respect, Christians have to reject one of the dominant assumptions of our culture. But the virtue of chastity, and the discipline of continence, should be demanded of heterosexuals just as much as it is of homosexuals.

The best response to the rise of a sexually active (and activist) homosexual subculture is the development of a culture of life where personal chastity and purity are universally encouraged and supported, where the dignity of the single person is fully acknowledged, and where chaste same-sex friendships are recognized and valued as a gift of God.



1 It can, of course, be annulled; but this merely constitutes recognition by the Church that the marriage never really existed, owing to the incomplete intention of one or other partner or the failure to consummate. It is worth noting that such an indissoluble union could not conceivably be brought about simply by an agreement between two consenting adults; that is, by legal contract alone. A mere contract, as distinct from the stronger form of personal union sometimes signified by the word "covenant", can always be dissolved. In fact it is highly unlikely that most of those currently campaigning for same-sex "marriage" want such unions to be indissoluble in that sense. Almost certainly they would permit divorce by mutual agreement, or even unilateral divorce in the case of cruelty or betrayal by one of the partners. But without indissolubility at least in principle, there is no "marriage" in the full sense understood by Catholics. The Orthodox tradition also regards marriage as indissoluble in principle, and divorce as a sin, though it allows more scope for the recognition of failure in marriage and the possibility of remarriage in some cases. back

Further reading
David Morrison, Beyond Gay (Our Sunday Visitor Press, 1999)
David Morrison, Homosexuality – Christ Above All: The Church's Teaching on Same-Sex Attraction (CTS "Explanations", 2004)
Livio Melina, "Homosexual Inclination", Communio Spring 1998 (also available in the Archive section of the Second Spring web-site.
On the whole question of chastity, see
For further information and help: couragerc.net and www.truefreedomtrust.co.uk.

This article appeared in the May/June 2005 issue of Faith under the title "The Church and Homosexual Marriage"