The question of homosexual marriage presents us with an inescapable moral challenge. The words, "homosexual" and "marriage", are inherently contradictory. The very fact that these terms are in public conflict demonstrates the radical character of the social revolutionaries who now demand the legalisation of homosexual marriage.

For at least the last 100 years, America has experienced an unprece­dented season of social transformation. Now, this transformation has been extended to experimentation with the most basic institutions and principles of our common life. A conversation about "homosexual marriage" is only possible if the concept of marriage is completely redefined and severed from its historic roots.

Civilisation requires the regulation of human sexuality and relationships. No society — ancient or modern — has sur­vived by advocating a laissez faire approach to sex and sexual relationships. Every society, no matter how liberal, sanctions some sexual behaviours and proscribes others. Every society estab­lishes some form of sexual norm.

Pitirim Sorokin, the founder of sociol­ogy at Harvard University, pointed to the regulation of sexuality as the essential first mark of civilization. According to Sorokin, civilisation is possible only when marriage is normative and sexual conduct is censured outside of the mari­tal relationship. Furthermore, Sorokin traced the rise and fall of civilisations and concluded that the weakening of marriage was a first sign of civilisational collapse.

We should note that Sorokin made these arguments long before anything like homosexual marriage had been openly discussed. Sorokin's insight was the realisation that civilisation requires men to take responsibility for their offspring. This was possible, he was convinced, only when marriage was held to be the unconditional expectation for sexual activity and procreation. Once individuals especially males are freed for sexual behaviour outside of marriage, civilisational collapse becomes an inevitability. The weakening of marriage — even on heterosexual terms — has already brought a harvest of disaster to mothers and children abandoned in the name of sexual liberation.

The regulation of sexuality is thus a primary responsibility of any civilisation. In their review of Western civilisation, Will and Ariel Durant noted that sex is "a river of fire that must be banked and cooled by a hundred restraints". The primary restraint has always been the institution of marriage itself an institution that is inescapably heterosexual and based in the monogamous union of a man and a woman as husband and wife. In postmodern America, the fires of sex are increasingly unbanked and uncooled.

In a very real sense, marriage becomes the civilisational DNA of our social genetic structure. Beyond this, marriage serves as the basic molecular structure for human social organisation. Though the family is extended through children and other bonds of kinship, the basic "molecule" of human society is marriage. This molecular reality implies that the structure cannot be changed without destroying the molecule and the organism itself.

This is precisely the challenge we now face on the issue of what is called homo­sexual marriage and the legalisation of same-sex relationships. The "molecule" of marriage has always defined human relatedness, and this most venerable institution is rooted in its inherent heterosexuality.

The family has undergone transformations throughout time, but at the core of any enduring family structure stands the integrity of marriage as an institu­tion and the stability of marriage as an expectation both within and without the marital unit. Marriage is always both a private and a public matter, and in Western cultures, it has stood as both a civil and religious institution. As such, it has been recognised as inherently and indisputably heterosexual.

The unique role of marriage in civilisation is rightly attributed to the social value any culture must place on stable long-term monogamous pairings of men and women. The institution of marriage has been invested with both rights and responsibilities directly tied to the social importance of long-term commitment.

The heterosexual union of a man and a woman in monogamous marriage is the rightful context for procreation. When reproduction is severed from marriage, the society reaps the breakdown of both kinship and parental responsibility. Put most simply, even secular historians are aware that marriage is what explains why a father remains committed to the care of his own children. Societies that devalue marriage provide an automatic incentive for young males to act irresponsibly, fathering children without ever assuming responsibility as father.

Marriage is indispensable for the successful nurture and raising of children. Both boys and girls define themselves and establish their own identity and expectations based upon their observa­tion of both father and mother, husband and wife male and female.

The extension of the family through other kinship relations links one marriage to another, with the entire family finding its identity and security in the integrity of those marital bonds. The breaking of these bonds leads to social dissolution as well massive economic, legal, and psychological ills. The integrity of marriage is essential for children to know the security necessary for their own self-identity and sense of belonging.

The central function of marriage has been reflected in law, custom, and an entire set of practices deeply embedded in the structures of society. These range from implications in the tax code to various legal supports and cultural expectations extended to the married couple. Society invests both rights and responsibilities in the institution of marriage and by its various incentives and disincentives, points towards a cultural expectation. When that expectation is something other than marriage, problems immediately arise.

In its own interest, the government must value stability and reward the healthy raising of children and fulfilment of parental responsibility. To this end, the government does discriminate in order to reward and to support mar­riage as the centrepiece of self-government and the commonweal.

Government has within its power the ability to institutionalise its own expectation in the form of laws, regulations, and a cultural approach that either strengthens or weakens the institution of marriage. Just as the tax code discriminates in favour of homeowners (because the government rationally sees homeownership as a common social interest), a set of financial and legal incentives is directed towards a social preference for marriage. In the same way, even as the law protects corpora­tions in order to encourage financial activity, the government also favours marriage (and thus married couples) in order to encourage procreation, childrea­ring, and cultural stability.

Nevertheless, government does not have the right to reorder this most basic institution of human organisation. Marriage predates the establishment of government, and any governmental authority that would presume to redefine marriage apart from its inherently heterosexual nature will do so at great peril. Furthermore, advances toward legal recognition of same-sex relation­ships have been propelled by the action of courts, rather than legislatures. This is another example of the "judicial usurpation of politics" that threatens the integrity of democracy itself. A gov­ernment that would claim the right to redefine marriage in this way demonstrates an arrogance that would cause Rome to blush and Babylon to quiver.

Inevitably, once marriage is redefined as something other than a heterosexual pair, there is nothing to stop further redefinition but sheer arbitrariness.

Once marriage is no longer "one thing", but now "another thing" as well, there is nothing to stop marriage from becoming virtually "everything". Put simply, if marriage can be redefined so as to allow same-sex pairings, there is nothing in the logic of this transformation that could justify discrimination against those who would transform marriage in other ways. Why just two people? If the consent of all partners is all that is requisite, why do we have laws against incest, polygamy, or any number of other alter­native arrangements?

Marriage has already been weakened to the point of dire social peril. The acceptance of "no-fault" divorce laws, the ethic of sexual liberation, and even the rise of new reproductive technologies have weakened the foundation and superstructure of marriage to the point that this most basic molecule is hanging together by a thread. The redefinition of marriage in order to accommodate same-sex relationships would not mean the mere transformation of marriage but its dissolution. The very concept of mar­riage cannot survive such a denial of its inherent meaning and historic structure.

Of course, I speak as a Christian theologian. Based upon divine revelation, I believe and teach that God created man and woman in His image, created us as male and female to His glory, and gave us the institution of marriage for our health, our happiness, and our holiness. Furthermore, based upon this same rev­elation — the Holy Scriptures I am absolutely bound to declare the inherent sinfulness of all sexual activity outside of the marital bond. Procreation, reproduc­tion, child-rearing, and other essential rights and functions are divinely invested in the institution of marriage. Thus, to tamper with this divinely estab­lished institution is to risk not only social peril but divine judgment.

Nevertheless, even those who do not share my Christian commitment must recognise the cultural wisdom and historic knowledge that points to the primacy of marriage and the disaster which will befall a society that would weaken — much less destroy — this most precious institution. The historic wis­dom of human happiness and moral knowledge points to the centrality of marriage. A review of history proves its necessity to civilisation itself. Marriage is a given — and is therefore not infinitely negotiable. Marriage cannot be severed from heterosexuality without dissolving into meaninglessness. Social experimentation must meet some limitation and the controversy over same sex marriage presents us with that limitation.

Homosexual couples cannot fulfil the functions of marriage. They cannot pro­create. Severed from even the possibility of natural procreation, their relationship is inescapably unnatural. Rather than reinforcing heterosexual responsibility and sanctioning heterosexual monogamy, same-sex sexual pairings undermine the very notion of a sexual norm. Acceptance of homosexual marriage flies in the face of both biblical revelation and millennia of accumulated moral wisdom.

This nation stands at a dramatic moment of decision. Our stewardship of this question — our decision on the question of same-sex marriage will determine the future state of our society, the moral status of our culture, the health and wellbeing of our children, and the inheritance we leave to the world. The choice before us is not between two visions of marriage but between mar­riage and madness.