Christmas Eve and Christmas Day see churches unusually and unnaturally crowded; these are the only days incumbents pray for naves and aisles to be extended by a bay or two. For the rest of the year, Britain has a surplus of churches; they are places for looking around, not for praying in, the stuff of Pevsner's architectural guides, tourist brochures, Merchant Ivory films and cosy television documentaries.
In fact, it is hard not to wonder if we really want the churches we already have, let alone whether we should be building more of them. A small fortune in heritage lottery funds has been making its way in recent months to shore up the ruins of our Christian past; it is not spirituality we are nursing with our millennial millions, but sentiment, nostalgia, architecture washed down with a teaspoon of guilt.
Our new cathedrals are air-conditioned shopping malls and superstores, theme parks, leisure centres, sports stadia, museums and art galleries. We have built almost no churches over the past 50 years to compare with those of the past 1,000 years, while those religions and cults that have prospered over the same period - whether Islam or Christian fundamentalist sects and schisms - have, as yet, built nothing of any real beauty. The Hindu temple on the North Circular Road, Neasden which has attracted so much attention over the past year is an impressive work of traditional Indian craftsmanship, but is not great architecture.
One can argue that we no longer need impressive settings in which to worship, and have not done so since the Reformation. This, however, does not explain the many couples planning to marry, the parents thinking of christening a new child or the families dreaming of an old-fashioned, picture-postcard Christmas, for whom a lovely old church is as important as the event itself: the quality of church architecture is high on their list of priorities.
Again, sentiment (and taste and prestige) plays a much greater part on these occasions than any new-found spirituality: after all, a child can be baptised under a kitchen tap, a couple can get married on a fishing boat and Midnight Mass can be terribly disappointing if you are expecting the full works (bells, smells, choirs, cherubim, etc) and find tambourines and cheesy modern hymns instead.
No, we do not need to build more churches or places of worship; our money is better spent elsewhere. What we might want to do, however, is to consider what use we could make of the thousands of underused or redundant churches that decorate these islands so richly and so woefully.
They can, of course, be deconsecrated, sold off and turned into fanciful middle-class homes. Or they can be re-addressed by artists, architects, local people and even the clergy working together on projects that will make people want to visit these lonely buildings and nourish the apparent need for a sense of spirituality lacking in so many lives, a latent spirituality that can never be satisfied by embarrassingly bad modern services, electric candles and hymns with lyrics that can make the soggiest and most sentimental liturgical liberal cringe.
This autumn, the abandoned and secret Oratorio di San Ludivico in Venice has been home to a beautiful, inventive and moving art installation created by Pierre d'Avoine, an architect living and working in London with the artists Heather Ackroyd and Dan Harvey. The installation, Host, was one part of a trilogy of exhibits going under that name in different parts of the city.
What d'Avoine and co gave shape to was a living, breathing representation of an elemental temple or church inside a redundant chapel. Visitors with sufficient guile to find the oratorio, tucked at one end of a passage no wider than Stella Tennant's shoulders and hung with washing from flats on either side, opened the creaky door and found themselves confronted by what appeared to be a primitive Greek temple made of wet and vibrantly green grass growing from the centre of the chapel and nearly filling it.
In the artists' imagination, the old oratorio was host to this mysterious organic architectural newcomer; it was as if the old place of worship, in rotting away, had given the last of its spiritual energy to sustain this new growth.
The result was powerful, a little shocking (as great church interiors often are) and uplifting at the same time. The grass temple was made of timber, covered in mud and planted with pre-germinated seed grass; watered every day, the sweet-smelling grass grew lustrously and this beautiful intrusion made its presence felt ever more strongly.
The temple was so designed that when people walked into the oratorio, they passed under its hollow, black-painted belly and only became aware of what had happened to the chapel as they explored its green edges. Host worked in much the same way as a grand religious procession through a church does, or a group of animated statuary in a Baroque chapel - it filled the sacred space in a numinous way, resurrecting its latent spirituality.
The fact that the design was also a reference to Palladio, to the nature of Venice and the origins of architecture may well have been lost on (or failed to have got across to) most visitors, but this hardly matters. What Host proved was that we can bring vigorous new spiritual life and new forms of architectural beauty to forgotten and abandoned places of worship.
By encouraging architects and artists to transform churches and chapels for brief periods, we might encourage very many people to visit them for whom they are little more than outmoded architectural curiosities.
The idea of the Host project would translate well to British churches, although bodies such as the PACA (Public Arts Commissions Agency), which commissioned d'Avoine so successfully, will have their work cut out uncovering artists and architects who can add spirit as well as art and cleverness to beautiful old buildings. This, however, would be a much more interesting and rewarding challenge than simply trying to add to the stock of a type of building we say we want but so few of us use.