How did we decide what Christ looked like?

This National Gallery exhibition has a catalogue of extraordinary splendour and is accompanied by four programmes on BBC2’s new Art Zone slot. In the Gallery itself there are further aids to understanding in the form of a film show, CD-Roms and audiotapes. A BBC book accompanies the series, and Neil MacGregor, the indefatigable director of the Gallery, not only does the TV presentations but is making a hectic lecture tour (Glasgow, Liverpool, Cardiff, Belfast: admission free). We are talking about as professionally orchestrated an art offensive as we are ever likely to see.

The title of the show has a faintly evangelical ring, but its avowed purpose is not to proselytise. MacGregor remarks in his catalogue introduction that one third of the paintings in the National Gallery (and in comparable institutions) are of Christian subjects, though it is improbable that even one third of the people who go to look at them would call themselves Christians. The paintings don’t really belong in Trafalgar Square anyway; at some time in the past they were removed from churches and other places where they had a clearly understood devotional purpose. But there they are, unmistakably still dedicated to that purpose, though it is a purpose no longer clearly understood. Most of us look at them with some quite different, ill-defined, but un-devotional motive.

Seeing Salvation is anxious not to put us off; if we don’t take a Christian view we are allowed to think of the pictures as representing ‘part of a narrative of human artistic achievement’. But that sentiment is a vague substitute for intimacy with the original theological certainties and subtleties, which the experts understand and which some of them may well think consistent with their own religious positions. Conventional pieties do occasionally peep through the prose of the catalogue and the TV commentaries, where they are rather heavily underlined by John Tavener’s music for the title sequences.

Still, the organisers encourage us to compromise, to substitute human for theological concepts, to accept the life and sufferings of Christ as ‘archetypes of all human experience’, conveying truths not just to Christians but to everybody. For example, Piero della Francesca’s Baptism of Christ (which we see in the rather enigmatic run-up to each TV segment) is ‘an epitome of compositional values’ but it is also ‘an exploration of the central mystery of the Christian faith – the total fusion of human and divine’.

I doubt if this really works. You may well think The Baptism a beautiful painting, but it has a cause and a purpose, a sense that cannot be had without some theology. A striking example of such senses is the convention, alluded to here, whereby the genitals of the holy child are emphasised in various ways. The purpose is to insist on the fully mortal nature of the fully divine child, but we had so totally lost touch with the idea that it required Leo Steinberg’s remarkable book The Sexuality of Christ in Renaissance Art and in Modern Oblivion to restore it to our notice. Or we might miss the homiletic point of pictures showing St Francis embracing the Christ child, or the dead Jesus, and have to be told that it ‘calls on each one of us to embrace the incarnate Christ’.

It is true that the explanations of the experts often make the pictures more interesting without diverting our attention from their formal beauty, but it might have been better to admit that a full understanding of their structure demands an acquaintance with the language and symbolism of Christian devotion and theology. This understanding can be acquired without me slightest degree of religious complicity. The exercise is familiar to people who study not only paintings but poetry, which draws on bodies of ideas that most of us no longer have at first hand.

In elucidating complex paintings the catalogue and the TV presentations do a very good job. The mistake lies not in the argument that the Christian tradition provides ‘a series of archetypes’, but in going on to say: ‘that is why Christian imagery is universal.’ The archetypes treat of suffering and death, and in that are like many other archetypes and deal in experiences of which nobody will deny the universality. But there are aspects of Christian imagery that are not, in this sense at any rate, archetypal – the dual nature of Christ, the doctrine of the Trinity etc. The move towards a humanist-Christian concordat is not that easy. There is a fundamental difference between the kinds of devotion each side is prepared to offer.

As MacGregor points out, the arrangement of the exhibition is unusual in being topical rather than theological. Under the heading ‘Sign and Symbol’ we find wall paintings from the catacombs along with much later paintings, not only Zurburán but Holman Hunt. Roman coins are placed in the same tradition, the same gallery, as Philip Webb’s beautiful William Morris-inspired Cross of 1897. Other sections on ‘The Dual Nature’ and ‘The True Likeness’ offer similar comparisons between works far apart in time.

Yet one cannot help seeing the show chronologically. For example, there is a clear temporal divide between art that made no attempt to offer likenesses of Christ and art that counted on everybody having an idea of how he looked. In the early Christian centuries the need didn’t exist. St Paul wasn’t interested, and the Judaic tradition was opposed to images anyway. The conversion of Jesus from an itinerant Jewish charismatic to the Logos, the second person of the Trinity, was made later by philosopher-theologians in the Greek tradition to whom the physical appearance of Jesus was not an important consideration.

Our attention has therefore to be directed first to the earliest Christian art, those wall paintings in which Christ is not portrayed but represented symbolically, sometimes, but rarely, by the cross, still a symbol of shame unless converted into an anchor, a symbol of hope; often by a fish (ichthys, ‘fish’, is an acrostic, its letters standing for Jesus Christ, the Son of God); or just the first two letters of the name, chi rho, XP, Christos, will suffice, often placed between the Alpha and Omega of Revelation 1.8. The Latin version of the first three letters of the Greek name, IHS, were read as signifying Jesus Hominum Salvator. The monogram constructed on chi rho may be crudely carved, or worked into rings and coins. We are shown a rather wonderful bronze lamp incorporating a chi rho sign which its light will project as a shadow on a wall. Later Christ is represented as a human figure, but allegorically, in the guise of the Good Shepherd.

The absence of interest in the personal appearance of Christ was matched by a general indifference to the Gospel narratives. Signs and symbols were enough. Later, when the narratives came into prominence, the emblematic habit did not fade away: indeed, the stories yielded still more symbols and emblems. A charming fourth-century catacomb wall-painting shows the Magi on their way to adore the child, striding forward, in step, with their presents in their hands. This exhibition allows one to set this faint, charmingly simple image alongside a grand early 16th-century altarpiece by Jan Gossaert, or Breughel’s sour, sad Adoration of the Kings half a century later, each with its worked-out theological symbolisms. The third royal gift, myrrh, was used in preparing bodies for burial, and Breughel’s child shrinks from it as from a premonition of his death. The other gifts, gold and frankincense, signify kingship and divinity; and so on. Episodes from the life are now loaded in this way. Murillo places the holy family so that the child is part of an earthly trinity yet also part of a heavenly one – the theology of the dual nature, something on which we may need instruction.

Elaborate Christmas cribs were made, and often contained dolls, so that the rich owner’s family could imitate St Francis, pick up the child and adore it The emphasis being steadily on the Incarnation, the mortal nature of the child is always relevant. Robert Campin’s The Virgin and Child in an Interior, of about 1430, fills what may look to us like a simple idea with recondite symbolisms: even the position of the child’s left hand is important, for he touches his mother’s face with a conventional lover’s gesture, while his right hand draws attention to his genitals, an image of humanity displayed without shame. He may also be indicating his circumcision, which prefigures his later sacrifice.

Perhaps an increasing concentration on the Passion narratives was what stimulated a demand, not least among painters, for a likeness of the protagonist. The account given here of how a received idea of Christ’s appearance was established is one of the most absorbing parts of the show. The need was met at first by the recovery of the kerchief, napkin or sudarium offered to Jesus by Veronica as he carried his cross to Calvary; it was found to bear a miraculous imprint of his face. The most venerated of relics, it was displayed in Rome for the benefit of pilgrims, and it was endlessly copied; there were recognised trades of veronica-makers and vendors. The fame and authenticity of the relic were supported by a letter supposedly written by a Roman governor of Judea in the time of Jesus, actually a forgery of the 13th or 14th century. Veronica herself acquired a saintly biography. Her napkin appears in some extraordinary paintings, including a trompe l’oeil piece by Zurburán which cannot have been very like the copies sold outside the churches; it defines the point where the devotional yields to the demands of virtuosity.

In the East a similar image, called the Mandylion, was preferred. It is attested in sixth-century Byzantium, and its authority stemmed from its being acheiropoieton, ‘not made with human hands’, a virtue obviously transferable to the veronica. Later came the Turin Shroud, recorded in the 14th century and still disputed.

Our received idea of the face of Christ owes most to the veronica. Its arrival on the scene is related not only to a growing interest in the appearance of Christ but to the developing demand for indulgences. The point of indulgences was to shorten one’s time in purgatory, and it seems that in the late Middle Ages people went about doing so in a very business-like manner, storing the indulgences they had collected by many different methods. Eamon Duffy in his great book The Stripping of the Altars says the accumulation of indulgences resembled ‘the transfer of credit to an overdrawn current account from an abundant deposit account’, the latter created by the merits of Christ. To maximise your claim on that fund and speed your way through purgatory you made proper provision in your will. Masses were to be said, and relatives were urged to pray hard for you, especially in return for testamentary favours. You could order a ‘pardon brass’, which would ensure strangers’ prayers on your behalf. Duffy mentions a prayer which promises 26,000 years and 26 days’ remission.

What the Reformers called ‘deceitful and juggling images’ could be a means of achieving huge post-mortem benefits for oneself or for others. You could get 40 days’ remission by bringing a faggot to the burning of a heretic. To pray before the actual veronica in Rome, or even before a papier-mâché copy – the exhibition includes a rare and striking 15th-century Netherlandish survivor – was a sure way of gaining credit.

These extraordinary images, like the relics that kept the pilgrims on the move, were important to a spiritual economy which worked in quasi-commercial ways and in which the work of artists had an important place. But the artists, makers of the images, had an interest that was not specifically religious. In the 17th century Claude Mellan made a virtuoso print image of Christ’s face on the veil, executed in a single spiralling line starting at the tip of the nose. The devotion it promoted would be to the artist’s amazing skill rather than to the face of Christ.

We have come a long way from the acheiropoieton, a long way, too, from a time when insuring against too protracted a stay in purgatory was a day to day business transaction. In a way one regrets the loss. In those circumstances one could think of oneself as being subject to intelligible, even familiar rules, and of oneself as of the company of sinners whom, unless you were a saint, you would soon join there.

A fifth-century ivory casket divides the narrative of the Passion into episodes, but only in the 13th century did that narrative become more central to devotion and more important to artists. The Passion story could be divided into separate but overlapping topics. Concentration on the detail, realistic and symbolic, of these episodes – the Crowning with Thorns, Ecce Homo, the Man of Sorrows, the Flagellation, the Crucifixion, the Deposition, the Entombment etc – coincided with a developed emphasis on the humanity of Christ, as shown by his suffering. By now the viewer can be expected to supply the full narrative context from a part of it. It might be enough for the painter to display the Arma Christi, the hammer and nails and spear – devotional objects capable of suggesting the whole Passion. The emblematic habit persisted, and perhaps survives or is revived in such works as Graham Sutherland’s tapestry for Coventry Cathedral.

The exhibition demonstrates new ways of mounting exhibitions, and provides some striking juxtapositions. Watching the television series I couldn’t avoid the thought that new ways of doing that kind of thing are equally called for. The whole enterprise is lavish, but generically little different from the sort of thing Kenneth Clark long ago accustomed us to. Like Lord Clark, Neil MacGregor walks around or stands in front of all manner of splendid things and comments wisely about them. One has the usual vulgar frissons: did they really go to Seville to shoot a few seconds of that religious procession? How much did diose South American episodes cost? Now we, or anyway MacGregor and this team, are in Bamberg, now in Ravenna. The series is certainly a triumph of organisation.

It begins, after the enigmatic prologue, with MacGregor standing in front of a remarkably visible Leonardo Last Supper. The opening programme ends with the same image, which makes its iconic focus different from that of the exhibition. The TV series covers more ground than the static show. But there is something naggingly wrong about the way it’s done. MacGregor is a modest and personable explicator, but there he always is, instructing us in the modern understanding of ancient pieties, telling us that a painting ‘is not as straightforward as it seems’. What he says is full of interest. But what we see is always the Last Supper, or San Vitale, or St Francis receiving the stigmata, plus Dr MacGregor. It alters the picture. The technique goes back to the old lantern lecture, the lecturer clicking onto a new slide, waving his pointer. Of course it was refined by Lord Clark. How much would be lost, one ungratefully wonders, if it were done by voice-over? But that might remind one inappropriately of the old travelogue genre. It is a problem.

A lot of people who have to miss the show itself will be able to see the TV series. It’s worth the wear and tear on four Sunday evenings. In fact the entire co-ordinated project, show, catalogue and TV series, amounts to as serious an enterprise in art education as one could well hope for. And having niggled a bit, I ought to express my admiration for MacGregor and the other authors of the catalogue, and for the extraordinary enterprise of the people who made the programmes, not least the cameramen. They showed what in the circumstances was an appropriate secular devotion to the images under their eyes.