Anyone for sainthood?

A depiction of Princess Diana as the Madonna should not shock us. Her statue perfectly captures the spirit of the times

The transvestite is not simply a man or a woman in disguise but a new creature created in between the two. The same could be said of the limewood statue of Princess Diana created in the fake-Renaissance, fake- medieval style still beloved by old-fashioned Roman Catholic congregations. The statue is neither Diana, nor is it the Madonna. So breaking the taboos we have set in place to keep certain things firmly separate predictably garners hostility from all sides. And that is exactly what has happened to the new show at the Tate Gallery in Liverpool.

The show, Heaven, an exhibition that will break your heart, suggests that religious practice and devotion have now found their main outlets in popular culture. Catharine Braithwaite of the Tate says that the intention was to explore people's "inherent need to be religious". The argument is that if we don't express this through attendance at conventional church services we will find other venues - whether shopping malls or football grounds - that suit us better.

Accordingly, the works of art on display at the Tate in Liverpool, by international artists working in fashion, video, painting, digital imaging, sculpture and photography, embody the sacred through references to the profane. Modern-day versions of this ancient rite of pilgrimage, for example, feature in another exhibit - Ralph Burns's photographs of the crowds flocking to pay tribute to Elvis at Gracelands. Contemporary symbols of perfection include Karen Kilimnik's glossy pictures of film star Leonardo diCaprio and Jeff Koons's white and gold sculpture of Michael Jackson.

The exhibition, enjoyably tactile and sensual, appeals to an iconography of advertising and pop music that we are already familiar with, just as traditional Christian art relies on our supposed knowledge of stories from the New Testament. With this show, the two kinds of knowledge and stories inter-penetrate. It's not just that the profane imagery represents the sacred. The two have become utterly fused, to create a third term which didn't exist before.

The statue, which has been the focus of media attention, was commissioned for the show by Doreet LeVitte Harten from Art Studio Demetz, a company specialising in devotional statuary. The catalogue entry describes the piece as Lady Diana as a Madonna, and the statue has been accordingly howled down as desecrating the image of the Mother of God.

In fact Diana is not shown in any of the well-known poses or colours of the Blessed Virgin. Unveiled, with her hands clasped at her waist, without a halo or a circle of stars around her head, lacking a crescent moon and a serpent under her feet, she appears rather in the generic guise of the Lady Bountiful. There's even a suggestion of the patient, devoted St Joseph standing guard over the baby in the Nativity crib.

So why the fuss about this mild and unprovocative piece? After all, Diana has been popularly perceived as a saint for a long time now. The Bishop of Liverpool understands this ambivalence. He is reported as saying:"The exhibition reveals a culture that leaves God out of the picture while holding on to religious imagery and ritual." In fact God, believed to be an invisible spirit, doesn't come into Christian religious art all that much. He appears occasionally as an old man with a white beard, as a dove, or as a thunderbolt.

Christianity valued the spirit at the expense of the body, as it valued men at the expense of women, believed to be all body and little soul. Christian anxiety focused on the body and sex as the source of our ills, and of our ultimate death, and attached blame to women, who, by giving birth, made us vulnerable to death. Christianity therefore declared Mary an impossibly perfect and sexless mother.

We're supposed to adore her precisely because she's not like us. Not earthly. Chris Ofili's Madonna piece in the recent Sensation show offended some Christians by recombining "bad" earth and "good" heaven. Ofili's work literally gave back Mary her earthiness, being partly made of dung, and featured "pornographic" images as the return of Mary's repressed sexuality. Good for him.

Christians who want their female saints perfect and virginal will be outraged that Diana, the Princess of Wales could ever qualify. Saints are, however, initially made by popular acclaim. On the one hand, popular ideas of sanctity have moved on and become more tolerant, so that people are grateful to Diana for being flawed, and so like the rest of us. On the other hand, her enormous wealth and privilege become the proofs people need of her transcendence, her difference. Diana shores up notions of heaven as "up there" just as she simultaneously shores up the monarchy and the class system. The church need not feel threatened by this statue, which is far less subversive than the work produced by contemporary female artists such as the late Helen Chadwick, who, reclaiming female flesh as powerful and sacred, was not afraid to make beautiful pieces out of chocolate, blood and even urine.

The secular criticism of the Princess Diana statuette comes from its connection to kitsch. If admiring celebrity culture shows us to be superficial and mindless, the argument goes, then enjoying this combination of the head of a celebrity and the body of a Madonna, with all the references implied to mass-produced cheap and tacky souvenirs of the sort found at Lourdes, reveals us to be hopelessly sunk in tastelessness. Atheists, who can be deeply moral, and Protestants, who venerate the Word, often have very stern ideas, based on their love of reason and rationality, about what religion ought to be like. Catholics, brought up both to cherish and to disapprove of sensuality and sensation, flourish on contradiction and excess and cheerfully admit their affection for graven images. Poor non-urban, unreconstructed Catholics, that is.

The class system comes in here. Kitsch originated in Victorian times, Celeste Olalquiaga informs us in her recent book The Artificial Kingdom. Industrialisation and mass production meant that everybody, including the working classes, could collect cheap factory-made souvenirs. Snobs then decided that reproductions spoiled things, that only primary and original objects could convey immaculate and irrevocable meanings. Copies were devalued as shallow imitations, while "authentic" objects gained even more prestige.

But the value of kitsch resides in the mind of its buyer - what we call sentimental value. The best kitsch - or copy - has an aura of having been to some extent hand-made, like a first edition book or an old mechanical toy. Religious souvenirs are designed to be identical copies; that's their function. Yet the statue of Diana, mixing references to high and low art, looks as though it might just have been hand-carved, and perhaps hasn't been mass-produced at all. Perhaps that's another reason it irritates aesthetes so much.

Kitsch, by pretending to evoke the hand-made, evokes nostalgia for a pre-industrial natural paradise before the Fall. I think paradise is our fantasy of the perfect mother we all wanted, but never had. Of course fantasising about the Madonna epitomises kitsch. Which is perhaps why comfortably off, well-educated middle-class people tend to displace their longings for maternal icons into shopping for pashminas or pumice balls.