The Church of England has spoken. And apparently, we are against gay marriage. We are not "anti-gay", we hope you understand. After all, as the statement says: "We have supported various legal changes in recent years to remove unjustified discrimination and create greater rights for same sex couples." Oh, no. We are not homophobic. It's just that we (the straight religious people) think that if gay people are allowed to get hitched in church then that will ruin things for the rest of us. The presence of homosexuals at the altar, vowing lifelong love and fidelity, will devalue the institution of marriage. It would be like letting women join the Garrick.

Apologies for the sarcasm. But I am spitting blood about the latest ridiculous statement from the Church of England. First, it is worth exposing the straightforward lie that is expressed here – that the C of E hierarchy has been supportive of civil partnerships. It has not.

In the main House of Lords debate in June 2004 the majority spoke against it and voted six to one in favour of a wrecking amendment. The leadership of the C of E will do anything to keep gay people out of the church. It uses the sickly language of welcome but won't let gay priests (even celibate ones) become bishops and is prepared to cut the Church of England off from the Episcopal church in the US because they do. At every turn, the Church of England treats gay people as an unwanted headache.

The other shameful aspect about this statement is that it purports to represent the views of the whole Church of England. "How can a church that is so divided on this issue produce so one-sided a statement?" asks a contributor to the Thinking Anglicans web site. Quite. This statement has not gone before General Synod for any sort of discussion. It has not been discussed at diocesan level. It has been put together by small team in Church House, Westminster, who purport to speak in the name of many thousands of people who will think the whole thing is complete tosh. Those receiving this contribution in government need to appreciate that it has all the democratic authority of a President Putin election victory.

And finally there is the absurd hyperbole of the thing. "The greatest threat to the church in 500 years." Do us a favour. Worse than the dissolution of the monasteries? Worse than secularisation? It is telling evidence of the irrational fear that the church leadership has of gay people that they are prepared to make such ridiculous statements. And as a threat specifically to marriage, what about divorce? Unlike homosexuality, this is a subject on which Jesus was pretty specific, but the C of E is perfectly prepared to marry divorced couples. Indeed, they are perfectly happy to marry gay people too – just so long as they marry people of the opposite sex. For years, gay men and women have been pressured into lavender weddings and often lives of misery so as to live out a model of supposed respectability. The church has blessed these marriages, and blessed pets and battleships, but they won't allow gay people who love each other to make lifelong commitments in the sight of God.

The church is no more a cartel of moral wisdom. And those of us who still stick with it – though there are days like today when this is increasingly hard – do so in the hope that it can be called back to a deeper moral seriousness that is not in hoc to bourgeois notions of respectability and prejudice. This is not a great day to be a member of the Church of England. I am simply ashamed.

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