In Hegel’s formidable system of aesthetics, fine art fulfills its highest calling when “it has placed itself in the same sphere as religion and philosophy.” Philosophy, religion and fine art are modes of what Hegel called Absolute Spirit, by which he meant that each in its different way is capable of expressing “the deepest interests of mankind, and the most comprehensive truths of the spirit.” Despite his exalted view of art, Hegel felt that humankind had begun to outgrow it, and that it no longer provided “that satisfaction of spiritual needs which earlier ages and nations sought in it.” Thus he spoke grandly of the End of Art, which meant, in the long history of antagonism between philosophy and art, that a philosopher had once again found a way of putting art out of the way. Plato notoriously consigned art to the realm of shadows and illusions, and found no place for artists in the ideal society. Hegel, for his part, thought art belonged in the museum, where it would do no harm and function as an object for historical research. Since it is limited to the senses, Hegel argued, art is philosophy’s inferior when it comes to addressing the ultimate issues of being.

Much the same iconophobia inflected religion’s attitude toward art in the West, beginning with the Second Commandment, which assumes that we are unable to visualize things without worshiping the images. It was the genius of Catholicism to find a way of incorporating the impulse to visualize by monopolizing the production and use of images, which then made images natural targets for that religion’s critics. Iconoclasm–literally, the destruction of images–was a natural first impulse of church reform. “Church pictures,” Joseph Leo Koerner writes, “were accused of exciting idolatry, breaking the biblical law against graven images and ignoring the early Christian martyrs’ repudiation of pagan effigies.” Koerner’s subject, in this remarkable study, is “the reformation of the image”–how the artists of the Reformation, working closely with its thinkers, managed to reconfigure the devotional image to suit the needs of their religion, when the initial impulse was simply to cleanse the churches of painting and sculpture. They did this by effectively turning religious images into “visual equivalents of confessional texts.” The history of art in sixteenth-century Germany could have become “a story of the image’s annihilation.” Instead it became the story of the image’s transformation into something that did exactly what Hegel prescribed for art “in its highest vocation,” namely to situate art in “the same sphere as religion and philosophy.” Far from being limited to the senses, the art of the Reformation probed the deepest questions of human life. The art was intended to be read, one might say, rather than merely looked at or worshiped. It showed what the reformers, and most particularly Martin Luther, said. It mirrored devotional practice.

Koerner concentrates on two Reformation altarpieces. One is by Lucas Cranach the Elder in Wittenberg, which commemorates and portrays Luther twice, as he would still have been remembered by the congregation that worshiped in his church. The other is Heinrich Göding’s Mühlberg Altarpiece of 1568. Both of these extraordinary works were unknown to me, as I dare say they will be to most readers of this book. I knew of Cranach, but mostly from his earlier paintings of luminous undulating goddesses, whose luscious bodies are revealed through diaphanous garments fluttering against black Mannerist backgrounds. These hardly prepared me for a work as complex as his Wittenberg Altarpiece, let alone the Mühlberg Altarpiece, one of the most amazing works I have ever encountered. It is amazing because it manages to be art, philosophy and religion all at once. It fuses verbal and pictorial meaning in such a way that members of the congregation would be able to grasp, in a single visual experience, what they needed to know in order to see what they believed and understand what they saw.

Reading Koerner’s singular and compelling analyses, I felt that I could catch something of the atmosphere that Hegel must have breathed, sitting in the Lutheran church interiors of his native Saxony two and a half centuries later. It was as if that powerful metaphysician had somehow transformed that atmosphere into a speculative system in which art, philosophy and religion coexist in a unity as intricate as that of the Trinity. In a way, the Reformation altarpiece could be seen as the end of art, just as Hegel claimed. But in another way it is the beginning of art as we know it today, less an occasion for aesthetic delectation than of philosophical interpretation and understanding. Koerner writes that Hegel’s was the first aesthetic theory to be “based on meanings rather than forms.” But that is what the “reformation of the image” amounted to in practice.

Let us focus on the predella of Lucas Cranach’s altarpiece. A predella is a picture, or set of pictures, that rests on the altar itself and supports the altarpiece. It mediates, so to speak, between the physical space of the church and the pictorial space in which the persons of the altarpiece are seen. In Cranach’s case, the predella is a long rectangle that has the shape of a sepulcher, in which Luther is depicted at the right, preaching across a wide space to the congregation seated at the left. In the empty space between preacher and congregants there is an image of Christ crucified. Christ’s agony on the cross is the subject of the sermon, and Cranach has made this visible. But he has also made visible the fact that the Crucifixion is the meaning of the service, that it stands in the space in which the religion is practiced. This is not merely a vision shared by Luther and his congregants, for the Crucifixion is shown casting a shadow on the church floor, as if it were real. This situates it both in the hearts of the faithful and in the physical space they occupy. It relates the congregation to the altar and to the ritual mysteries that transpire there, as well as to the scenes depicted in the altarpiece itself, pre-eminently the Last Supper, in which Christ reveals that the bread and wine are his body and blood, and that he and his followers are one substance, as celebrated in the mass. In a stunning analysis of the painting, Koerner powerfully illuminates the complex of beliefs–theological, social and political–defining the religious practices that evolved through Luther’s teaching.

The predella of Heinrich Göding’s Mühlberg Altarpiece is, if anything, even more intricate. Seated before it, the congregation was able to see portraits, on either side, of the two patrons who commissioned the altarpiece. The predella itself shows them taking communion in front of the same altarpiece on which the predella rests. Since the predella shows the very altarpiece on which it rests, it shows itself in the picture. In this picture within the picture, there is therefore another picture of the predella, and within that yet another, in a diminishing series that in principle extends to infinity. By the time the Mühlberg Altarpiece was completed, Göding’s patrons had died. Yet the predella shows them in the same posture, partaking of the host over and over again, throughout eternity. It is as if the scene is reflected, re-reflected and re-re-reflected again and again, in what art historians call a mise en abyme–a kind of infinite regression in which a picture contains a picture of itself, which in turn contains a picture of itself. The most familiar example of this is the Quaker Oats box that shows a picture of a man holding a box of Quaker Oats with a picture of himself holding the same box, with a picture of himself holding the box, and so on forever. By depicting the pious couple in eternal communion with Jesus, The Mühlberg predella implies that those who take communion have already entered eternity. Nietzsche developed the idea of an Eternal Recurrence, which he claimed to be the most scientific of hypotheses. He believed that it would have an impact even greater than the doctrine of the soul’s immortality. Through repeating images of itself, the Mühlberg predella renders this highly abstract concept in strikingly visual terms.

The Reformation of the Image is the most exciting book of art history I have read since Hans Belting’s magisterial 1993 study of religious icons in European culture, Likeness and Presence. Both books not only introduce us to works of art of a kind with which we are likely to be unfamiliar but to ways of relating to art that are very different from those we take for granted. In both cases, the importance of the art in question does not depend on aesthetic merit. The devotional image, as Belting described it, was supposed to perform miracles if prayed to in the right way, not to gratify the eye. Only with the Renaissance did pictorial art make aesthetic gratification its central aim. The Reformation altarpiece found ways of picturing invisible things, the understanding of which was believed to be essential to salvation. Both authors draw liberally on philosophy to clarify the way these works functioned in venues very different from the museum and the art gallery. At the same time, these forgotten or little-known works reveal dimensions of artistic achievement that widen our understanding of art well beyond aesthetic contemplation.

With The Reformation of the Image, Joseph Leo Koerner has completed a three-volume study of German art that began with his earlier study of Caspar David Friedrich. Indeed, this volume opens with Friedrich’s 1807-08 painting, The Cross in the Mountains, which, like Cranach’s Wittenberg Altarpiece, leaves it unclear whether there is an actual crucifixion in the mountains or whether it is a vision of the Crucifixion in a wild landscape. The volume ends with an 1810 sketch by Friedrich of a ruined choir, a powerfully evocative Romantic image. Koerner interprets Friedrich’s drawing as “an allegory of how art arises from the ruins of religion.” What he has accomplished in this marvelous book is to bring that religion to life again, and in the process make vivid the art that emerged from the critique of images that launched the Reformation.