It has been a breathtaking transformation. When, in the 1990s, I climbed over the rubble that blocked the doorway, clambered along the ruined cloister and finally stood in the body of the church it was both awe-inspiring and dispiriting. Could this once-fine church designed by Edward Pugin ever be rescued from the dereliction into which it had fallen?

The glory days of Gorton's Monastery of St Francis, in inner-city Manchester, had long gone. The thriving community of Franciscans had been there since 1872 running three schools and a parish hall and serving mass to thousands every Sunday. The place was the spiritual centre of both the Irish and Italian families that lived around.

But in the 1970s the area was redeveloped; people were rehoused; congregations declined. In 1989 the monastery closed and was bought by developers whose plans soon folded. The pigeons, the squatters and the vandals took over.

Then in the 1990s a strong-minded woman led the rescue: fundraising, grant applications ensued. Along the way Elaine Griffiths restored some of the social good that the church had engendered: there were programmes for the old, the unemployed, even a programme for ex-offenders. It wasn't enough. There was a need for large sums of money and that meant approaching the big beasts of heritage restoration, in the UK and Europe.

As applications dragged, the fabric deteriorated further and costs rose to £7 million. The Heritage Lottery Fund (HLF) hesitated over the Monastery Trust's ability to deliver its proposed business plan. A sound business plan is at the heart of any attempt to get money from the public purse. So, with advice from the HLF, the existing plan was amended: the monastery would first become viable as a cultural centre and events venue. Conservation of the altar, some stained glass and paintwork was put on hold.

And so it was. By 2005 the work could start and the transformation began. The monastery now claims to be “the North's finest events venue”. It is once again a place of beauty and inspiration and it regularly hosts dinners, corporate celebrations, private parties and wedding receptions. And weddings? No, not weddings. Plenty of people from the local community and beyond have asked, but the rules say “no”. What rules are these that allow wedding receptions, but not the ceremony itself; that permit wedding blessings, but not the actual words that make a marriage legal? It all came about in 1993 when the passing of the Marriage Act allowed marriages to be solemnised on any premises approved for that purpose by the local authorities. The churches were the big losers. From then on people could marry in stately homes, hotels, concert halls and parks. There might even have been a wedding in a pod of the London Eye. But tucked away in paragraph 4 of Schedule 1 of the 1995 Marriage (Approved Premises) Regulations is a strange and prohibitive amendment:

“The premises must have no recent or continuing connection with any religion, religious practice or religious persuasion.”

Obviously, bewildered officials must have asked for clarification because the Registrar General issued further guidance:

“The secular nature of a civil marriage precludes the use of any building with a recent or continuing religious connection. This effectively rules out any building or room...still considered to be linked with religion. A chapel in a stately home and a building containing furniture or fittings associated with a place of religious worship or which has stained-glass windows depicting a religious image” would not be allowed.

There is no way the monastery is going to cease to look like a religious building. What's more, eager to conserve religious traditions, the trust has actually gone out of its way to acquire the Crucifix that hung high over the altar. The altar itself, still ruined but with a peculiar decayed beauty of its own, was not costed into the restoration.

To make matters worse that finely tuned business plan so necessary to the entire project had assumed weddings were part of the mix. The regulation might almost be judged in restraint of trade.

But the story gets worse. Many public art galleries are also keen to host weddings: helping along their business plan, too, no doubt. Dulwich, in South London, is one such. But again the ceremony itself must never proceed in any gallery hung with religious paintings. Dulwich's glorious collection of religious art includes a St Jerome by Veronese, a St Sebastian by Guido Reni and a glorious Madonna by Murillo. That's enough to drive any civil marriage ceremony into a humbler space where there is none.

I am not sure what to make of this crackpot regulation. But I sense that it is part of the on-going tensions between the religious and the secular interests in our society. Many discussions attend the drawing-up of laws and it could be that religious authorities asked that their abandoned buildings, deconsecrated though they are, should not be handed over for any civil marriage ceremony seen to be replacing one of the great sacraments of church life. I believe that they're missing a chance! At a time when there is a palpable sense that the values of materialism are proving shallow, it would be good to share places of beauty and inspiration with a wider public.

For many people today, religious buildings and paintings are part of the heritage rather than of the Church. But they are no less spiritual for that.

Joan Bakewell will be writing a fortnightly column

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