The agony, the ecstasy and all the stations that come between

The image of the crucified Christ has changed from victorious saviour to suffering God, says Richard Harries

The earliest surviving depiction of Jesus on the cross dates from about 420AD. It is one of a set of four small ivories in the British Museum, and it became more widely known through the Seeing Salvation exhibition at the National Gallery in 2000. It juxtaposes Jesus on the cross with Judas hanging from a tree, the 30 pieces of silver spilling out at his feet. On the cross, Jesus is strong and upright, facing the front, eyes open, and with his arms stretched straight out. This is no battered, defeated figure, but rather one in control of his destiny, winning the salvation of humanity.

Dating from about 70 years earlier, there is a sarcophagus, now in Rome, on which are carved scenes from the life of Christ. In the centre is a cross, on the upper half of which is a wreath of victory, enclosing a "chi rho", the first letters of the word "Christ" in Greek. Before Constantine won his decisive victory at the Milvian Bridge in 312, it is recorded that he saw a cross in the sky. As a result, he put the chi rho emblem on the banner, or labarum, of his legions. So here on this sarcophagus is a direct expression of the Christian conviction of the cross as a victory symbol. And the reason for this is made explicit in the rest of the scene for, at the foot of the cross, are two sleeping soldiers indicating that this is also the empty tomb. Christ's victory on the cross is validated and disclosed through the resurrection. The cross and resurrection are seen together as one integral conquest of evil and death.

Depictions of Jesus on the cross in the 20th century could not be more different. They are concerned above all to show a suffering Christ. Mark Chagall, in his remarkable White Crucifixion , now in Chicago, shows a number of scenes of pogroms against Jews, which he had seen for himself in the 1930s: synagogues being burnt, refugees fleeing to Palestine, jackbooted soldiers and so on. In the middle, dominating the painting, is Jesus on the cross as a Jew, a prayer shawl draped around him as a loin cloth, with a scarf as head covering. In Western Europe, Christians had made the cross an object of hate through their persecution of Jewish people. Here Jesus, as a Jew, suffers with his own people.

Chagall was Jewish, much influenced by M. M.Antokolsky, the 19th-century Russian sculptor, also a Jew, who saw Jesus as one in a line of biblical prophets. Antokolsky wrote: "Jews may have renounced him, but I solemnly admit that he was (a Jew) and died as a Jew for truth and brotherhood".

It is difficult to imagine a Christian artist depicting Jesus in that way, particularly since the Holocaust. Yet this is what Roger Wagner (born 1957) has done, with sensitivity as well as boldness. His painting Menorah , now on display in St Giles' Church, Oxford, is dominated by Didcot power station. The towers of the station form a seven-branch candlestick, the menorah, and the smoke billowing from them brings to mind the gas rising out of the ovens of Auschwitz. In front of the station are three small figures on crosses, while recognisably Jewish figures lament in the slanting, haunting light. The painting is visually powerful with its illuminated loam, on which the figures stand, and its stark blue sky. Its theme reverberates with sorrow and anger in the sensibility of 20th-century Christians and Jews.

The artist Stanley Spencer (1891-1959) expressed Christian themes throughout his life, albeit in a quirky, radical way. His most shocking study of the crucifixion is, characteristically, set in the high street of his home town Cookham, with two brewers' men gleefully banging nails into the hands of Jesus. Mary appears spread-eagled over a heap of builders' sand in the middle of the street. The painting had been commissioned for a school supported by a city livery company based in the brewing trade. When there was a row about the painting, Spencer was invited to speak about it at the school. In his talk, he emphasised the contemporaneity and universality of the human cruelty that crucified Christ. "It is your governors, and you, who are still nailing Christ to the cross," he said.

Many other 20th-century artists have depicted Jesus on the cross, but few have moved far from the theme of human suffering in which a suffering God shares. But the theme had appeared long before the 20th century. In the 11th century, it came as a shock to see a dead Christ, rather than one alive and victorious, on the cross. When Cardinal Humbert visited Constantinople in 1054, he wrote: "How do you come to fasten to Christ's cross the picture of a dying man?" But it should not have been such a shock because the poignant Gero crucifix in Cologne dates from the 10th century. From that time on, the emphasis on suffering has increased, mainly in response to the way the religious orders, especially the Franciscans, encouraged people to meditate by imagining themselves at the foot of the cross observing the pain of Christ for which they were responsible.

But the sense of a victory of the cross was never lost, so the crucified Jesus has also been depicted in a priestly role and with a crown on his lolling head. The 20th century finds this dimension particularly difficult. First, because of our extreme suspicion of happy endings and, second, because of our scepticism about miracles. Just how do you depict the victory of the cross or the resurrection of Christ today?

The early Roman Catholic Church expressed a profound reticence before the actual resurrection of Christ. At first, it showed only the women discovering the tomb to be empty. Then there developed the wonderful symbolic anastasis, or descent into hell as it is called in the West, in which Christ is shown breaking the locks and bars of Hell, planting his cross in Hades and pulling free Adam, Eve and others. In the 20th century, a number of painters have sought to portray particular resurrection scenes: there is a fine supper at Emmaus by Ceri Richards in the chapel of St Edmund Hall, Oxford, and in Chichester Cathedral Graham Sutherland's Noli Me Tangere . The final station of Norman Adams's Stations of the Cross in St Mary's, Mulberry Street, Manchester, consists simply of a garden studded with little flowers and thin things groping their way upwards. In the middle, a purplish mist dissolves, and in the sky Klee-like shapes dance and sing. But the stations need to be seen as a whole to understand the integration of this final triumph with the preceding agony. The difficulty of being real about the human agony, with something of what Francis Bacon termed his "exhilarated despair", while conveying some hope to a tortured world, remains.

It is, however, past depictions of the crucifixion that emphasise suffering that most speak to 20th-century sensibilities, the most important being the 16th-century Isenheim altarpiece by Matthias Grunewald. The point at which this horrifyingly stark and cruel picture of Jesus on the cross became prominent can be pinpointed to 1918-19, when it was shown in Munich. It reinforced a 20th-century German self-image of an anguished, martyred, angst-ridden people and had a significant influence on German Expressionism.

But for many people, it is the depictions of the Passion by Georges Rouault (1871-1958) that are most eloquent today. Rouault gave one of his paintings a quotation from 17th-century philosopher Blaise Pascal: "Christ suffers until the end of the world". But in addition to suffering, Rouault's paintings of the crucifixion have poignancy and convey a sense of pity.

They have a sad gentleness that is not without its own hope.

Richard Harries is Bishop of Oxford and author of The Passion in Art, published by Ashgate, £16.99. He will speak on Images of the Passion: The Spiritual Dimension in Art at the Winchester Art and Mind conference, March 10-13. www.artandmind.org.