I am reading Ivan Illich's 1987 essay "Hospitality and Pain" (freely available to consult here) which concerns the Western conception of pain and the body.
Illich claims, on page 13, that, after the first millennium, a transvaluation of the Incarnation and the Passion occurred in the West. He suggests that the earliest artistic depiction of the crucifixion emerges in the Rabbula Gospels and draws attention to the way Jesus is depicted as bloodless and with eyes open.
All the Gospel details are depicted: The two thieves, the soldiers throwing dice for the cloak, Longinus with the lance, Mary the mother and John the beloved apostle, the mourning women, the sun and moon hiding their faces. But the figure of Jesus is a symbolic iconogram rather than a picture. Unlike the naked thieves, he is veiled in the long mantle (columbium). The breast wound shows that his body is dead. But his open eyes and the halo around his head reveal the glory of divinity ever present in this body. The work is a Christological statement of the Council of Chalcedon: There are no signs suggesting torture or pain.
In the first millennium, Christians do not focus on the bodily pains suffered by Christ in his passion. Certainly one reason for this is the fact that they had no term fitting the word field of modern English pain. Pain directly denotes an ache in the body, and only obliquely emotion or feelings. The Greek words, lype, algos and nosos directly mean a state of the soul. And the Old Testament, one long story of woes and miseries in which Israel comes to recognize the hand of the living God, simply has no one word that directly refers to the body in pain.
Illich then briefly traces a history of the portrayals of Christ on the cross, describing how, in the 7th and 8th centuries, Jesus is typically veiled in a colobium sindonis, "sometimes reminiscent of the vestments of a priest or king." A century later, Illich claims, Jesus is now undressed down to the loincloth; from the 9th until the 11th centuries, the naked body is found in art, but not commonly.
A break occurs in the 12th century - Illich claims the body is now "even more important than the cross." (page 15)
But then, within Hildegard's generation, the iconogram of the Savior gives way to the realistic representation of a tortured man. As far as excruciating pain can be pictured, it is shown above every altar during the late Middle Ages. Once more the history of the perceived body, and the history of bodily pain, together pass a watershed. Just imagine the crucifixion of the Isenheim altar, painted by Grünewald, which I mentioned earlier. The limbs of Jesus are gangrenous, contorted, discolored - like those of the dying patients, to whom the indescribable light that infuses the painting speaks of themystery of salvation through pain.
In conversation with David Cayley in 1988 (see transcript here) Illich makes reference to these same ideas and summarises his point on how compassion, as a lived experience, becomes possible only at that historical moment when pain has been disembedded from the huge and varied matrix of suffering in which it had been diffused:
In 1100, the crucified Christ, who is one of the most important representations which are left to us of what people thought about the flesh, is still very much the Christ of the first millennium. The first 300 years of Christianity knew absolutely no crucifix. From then on, until the 11th century essentially, he who is on the cross is dressed up as a priest, is a person alive, crowned by the sun. Even if his heart is pierced and the blood flows out, you can see that he’s a fully alive person. It’s an icon, an ideogram. It is not a body which is represented. In the 9th century, slowly the clothes of the priest, the king, the columbium, as they call it, disappears from the body and he is represented in his nakedness, but still as a live body with eyes which look at you, even if his heart is opened. By the end of the 12th century, his head is inclined--he’s a dead man. His body is shown tortured. Physical pain is represented as acutely as you can possibly represent it. No wonder twenty years later, Francis will go and begin to kiss the wounds of lepers. No wonder Francis of Assisi will feel a new feeling for which there was no real word nor importance, even in Christianity, compassion so strong that the suffering with the suffering Christ will express itself written on his hands and feet as stigmata, and the epidemic of stigmata will appear all over central Europe.
Illich is a reputable historian but I have tried looking for depictions of the Crucifixion from before the 12th century and had a very difficult time finding any examples. In one word: is there any significant truth to his thesis that Christ on the cross was depicted initially robed and "alive" and then a sharp break happened around the 12th century, with Jesus now seen as a pained, hurt body?