... marriage 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.and in opposing proposals that would allow same sex couples to have a married status (rather than a civil partnership status that is currently possible in the UK) that is legislatively and culturally identical to that of married men and women.
However, the debate is not without its implications for the life of the Church, ad intra. The passage in St Paul's letter to the Ephesians - "Wives, be subject to your husbands ... Husbands, love your wives ..." - does not speak of marriage except in reference to the relationship between Christ and the Church. Indeed, in verse 32 St Paul almost goes as far as to say that, actually, the important point in all of this is that it has to do with Christ and the Church:
This is a great mystery, and I mean in reference to Christ and the Church (RSV)So the relationship between man and woman in marriage, for the baptised Christian, represents the relationship between Christ and the Church. Witness by the Church to the nature of the male and female relationship in marriage is, therefore, not just about a witness to a truth of natural law for the correct ordering of human society (this the significance of that witness for the public debate about same sex marriage); it is also a witness to the very nature of the Church herself. What is at one level about the social and political is at another level profoundly a question of theology/ecclesiology. Recognising this intersection of the social and theological in the question of marriage is important for the Church, since it demonstrates that she can do nothing other than oppose the idea of same sex marriage in the spheres of culture and legislation, or she would not be true to her own nature. It would also be helpful if those outside the Catholic Church were to recognise this intersection of the theological and the social, as it would enable them to have a better understanding of the contribution that the Church is making to public debate on the subject.
Hans Urs von Balthasar ends an essay "A meditation on Ephesians 5", an essay first delivered as a contribution to a seminar in 1978 commemorating the 10th anniversary of the publication of the Encyclical Humanae Vitae, with the following:
Let us end with this observation. For sexuality as Christians understand it - sexuality that takes as its norm the relationship between Christ and his Church - Christ's words hold true: "Let him grasp it who can". But Christ is saying something more here than that very few men and women will actually grasp his doctrine. He is issuing us a challenge to serious endeavour, the same challenge, essentially, that rings through the whole of the Gospel: Take up your cross every day, sell all you possess, and do not cheat as did Ananias and Sapphira. Why should the sexual area alone offer no challenge to the Christian? Sexuality, even as Eros, is to be an expression of Agape, and Agape always involves an element of renunciation. And only by renunciation can the limits that we set on our own self-surrender be transcended.The debate about same sex marriage provides the Catholic Church with an opportunity to renew her own self-understanding, and to evangelise those of her community who have become less and less conscious of the ecclesiological signficance of the Sacrament of Marriage. And, of course, to evangelise those of her members who dissent from the teaching of the Church on this matter.