The churches are hotting up in their opposition to gay marriage. The newspapers are digging in their positions – the Telegraph came out firmly against; the Times firmly in favour. But it seems to me that the position of the churches is rather confused, and logically they ought not to complain but simply to cease to recognise state marriage – indeed, probably ought to have done this long ago.
The idea of redefining marriage, removing the need for consummation by sexual intercourse, so that there is one type of "marriage" encompassing both straight and gay couples manifestly leaves us with a concept of "marriage" so enormously distant from the Christian concept that state marriage is no longer a form of Christian marriage – indeed, it could even be argued that the state marriage concept is not even a subset of Christian marriage, but actively in conflict with it such that churches should not merely not recognise state marriages but should actively discourage believers from participating in it. But that is not because gay marriage threatens the Christian concept of marriage. The churches have this quite wrong. Rather, it is only because state marriage is already so different from (and incompatible with) Christian marriage that the idea of modifying the marriage concept to include homosexual unions is even contemplated. Given what state marriage already is, there is no good reason for state marriage not to include homosexuals (but equally, no good reason why "civil partnership" should not be its legal name).
Traditional Christian marriage was a mystical union, ordained by God as a sacramental life-long covenant partnership. It existed to regulate sexual activity (with helpful by-products such as reducing sexual jealousy – the main motive for murder throughout history) and for the procreation, protection and rearing of children. Marriage pre-dated states – people were married in ceremonies for thousands of years before there were kings and laws of the modern form. But in Christian marriage even the priest does not do the marrying – a marriage ceremony merely solemnizes a marriage. The couple are joined in one flesh by God in sexual union. That is why there can be no unmaking of a marriage – one can be "divorced" in a state sense, but not in the fundamental sense, for what God has joined, man cannot separate, and God does not change His mind or make mistakes. (An implication of this is that a remarried divorcee like myself is actually fundamentally a polygamist – a point to bear in mind when one is inclined to become high-and-mighty about the evils of polygamy. Similarly, Christian churches have always recognised polygamous unions. For example, in countries where polygamy is legally permitted, those that convert to Christianity having already entered into polygamous unions are not, by the Church, permitted to divorce down to one spouse.)
Traditional Christian marriage, as a regulator of sexual activity, implied a permanent and ongoing contract of consent to sexual intercourse – traditionally there could by definition be no such thing as a rape within a marriage. (That was also much of the force of the so-called "buggery laws" – when you married she agreed to have sex with you, but she hadn't agreed to do just anything.) Failure to provide sex within marriage was a serious matter and indeed a motivator of public policy – during the Commonwealth, Cromwell was famously petitioned by Puritan women to ban the sale of coffee on the grounds that when their husbands drank too much coffee they lost sexual interest in their wives. Violating the sexual covenant in the other direction, through adultery, was a serious crime and violation of the Ten Commandments on a par with theft and murder.
The granting of any form of divorce / separation / annulment was a serious and rare matter – even in the late 19th century liable to be covered in the newspapers; earlier the sort of thing that led to wars and schisms and the establishment of new churches. If there were to be divorce, that was because someone was seriously in the wrong – e.g. an adulterer. The wronged party would have all the sympathy, retain property and dignity and children, and the party in the wrong would face serious sanction.
State marriage has removed almost all of this. There is almost no connection left with sexual activity, with contracts about sexual activity, or with justice of any sort in a state marriage. The state does not recognise contracts of permanent consent to sexual intercourse – rape within marriage is now conceptually possible and a crime. Violating the covenant through denial of sex within marriage is no longer a matter of public policy; indeed it now barely even qualifies for stand-up humour. Violating the covenant through adultery carries no legal sanction and virtually no social sanction – it makes no difference whatever, for example, to the allocation of children in a divorce. The state does not see marriage in terms of a contract regulating sexual activity – it does not believe it is the role of the state to intervene in people's sex lives, telling them that they ought to have sex with A because they promised to do so or they ought not to have sex with B because they promised not to. All that remains are a few details in the law about consummation – but these are nothing more than an echo of a bygone age.
And aside from a few eccentrics, virtually no-one regrets any of this. How many of you, Dear Readers, would want to go back to locking people up for adultery or telling married women they had agreed to have sex with their husbands and so could not be raped or to allocating children and property to the innocent party in a divorce?
State marriage is not today anything to do with regulating sexual intercourse. It is simply a bundle of contracts about matters such as inheritance, next of kin for medical purposes, pensions, and so on. It is not the solemnization of a mystical union of two people joined in one flesh in covenant partnership. So there is no good reason for churches to object if state marriage encompasses homosexuals, allowing them to bundle their contracts in the same convenient way.
And of course, the corollary of all this is that when people enter into a state marriage, they do not enter into a Christian marriage. So if churches want people to be married* (where "married* = Christian-married") they will have to do it themselves.