It's been unwell for a while. The Church of England isn't as popular as it once was, and although one million people attend its services every Sunday that's just 1/60th of the population. Seeing as around 70 per cent of us say we're Christian, that's a massive failure of getting bums on seats.
Now the church has decided to stake its survival on the issue of gay marriage, a move which is so obviously suicidal that it might be time to declare the Church of England mentally incompetent.
The Bishop of Leicester, Tim Stephens, is even worried that gay sex might not constitute legal consummation of a marriage because it's done differently, a bit like when Queen Victoria outlawed male homosexuality but not female because she didn't see how it would work.
It doesn't really matter whether you think two people of the same sex should be able to marry in church or that they shouldn't. There are gays who want to, gays who don't, and clergy who have spent decades thinking one thing or the other who find it pretty tricky to think something different.
The fact is that it's happening. It's out of our hands. Under the European Convention on Human Rights we can't not allow people to get married in church on the basis of their sexuality any more than we could not allow it on the basis of their hair colour, skin tone or body mass index, so it's past the point of arguing.
The church's rules were last used as the law of the land in the 12th century, when the Normans realised the Saxon court system was much better. The church split four hundred years later and accepted the monarch as their supreme head, and canon law was officially repealed in 1638 when some antsy bishops picked a fight with Charles I.
These days their boss is the Queen, and she has to agree to laws voted for by Parliament. So Parliament is legally, practically and constitutionally able to regulate the church. It's a bit late for them to wail about that fact 900 years too late.
It's also ignoring its own history. The church has managed to adapt and change because of a variety of other social changes, although it tends to take its sweet time about it.
It was formed in 1534 solely because Henry VIII wanted to get rid of one wife and marry another but it wasn't until 2002 the general public could do the same in a religious ceremony. It picked bits of the Catholic liturgy and Protestant theology to use as suited, Latin was banned and reinstated then banned again, and today atheists, Muslims and Catholics can all marry in the CofE.
But the bishops in charge of the church today have forgotten the past few centuries of its history in favour of concentrating on the rules of a book written 2,000 years ago, and their pig-headed refusal to admit they're not all as relevant as they once were is pushing the church towards extinction.
On the one hand there are die-hards who won't change one thing more and insist their god doesn't talk to women or endorse the love between people of the same sex; and on the other there are modernisers who want to inhabit the 21st century with a website and Twitter account which proudly boasts: "We're here to learn and to engage."
Right then, vicar. Pin your ears back and listen to this.
Gays exist, and if they want to get married in a church then you are going to be incapable of stopping them. Gays aren't illegal anymore, and our laws take precedence over yours. Because of those laws you usually marry anyone who asks, even Katie Price who's demonstrably not very good at it.
The Government says there are 3.6m gay people in Britain, which is three times your average congregation. They don't want to all get hitched, but there's more of them than there are of you so they're going to win this one.
Last time your church split it did so with a great deal of pain, death and difficulty but various bits managed to grow new life, like an amoeba that's been through a bacon slicer. But then you were a big, sprawling thing that could take the division. If it happens again you're so small that you won't survive; you'll be reduced to a scream on the wind.
Frankly you're lucky anyone's still paying you attention at all.
Gay marriage isn't undermining the church; it's undermining itself. It has to decide if it wants to exist, and if so to admit what everyone else has got used to - that there's nowt so queer as folk, and if it wants to minister to them it had better start enjoying that fact.
It needs new customers, and needs them sharpish. Straight people are marrying in fewer numbers than ever before so relying on them for the future is a business plan Alan Sugar would laugh out the door.
And if the church can't cope with that, then for God's sake please just commit suicide quietly.
"Hello? Is that Dignitas? How much for a job lot?"