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Visible Reminders of Invisible Light

West portal and nave of Chartres Cathedral (1194-1260), Chartres, France.

For most practical purposes, the glorious windows of Chartres are failures. Nearly all Gothic stained-glass windows are.

Looking out of these windows—dense collections of irregular bits of colored glass packed into thick metal webs—is impossible. If you could see through them, you would likely be rewarded with little more than a narrow view of the sky. Most do not open, so they are no help for ventilation. And since they let in less light than they would if they were transparent, they are not ideal for illumination.

Nevertheless, they are the crowning glory of the glazier’s art, triumphs of technology and the medieval Catholic spirit. If they fail to do what ordinary windows do, it is because they have been designed to do something very much out of the ordinary. They are windows in excelsis, bearers of light and beauty and meaning, meant to be looked at, not through. They are, in other words, not windows plain and simple, but true “picture” windows, elevated to the status of fine art, and brought to the service of God.

Instead of views of the world outside, they frame within themselves scenes of a world richly illuminated with meaningful symbols and sacred imagery, “very suitable for instructing the people in the faith. In them . . . the life of a saint, a parable, or some other biblical event [is] recounted. A cascade of light [pours] through the stained-glass upon the faithful to tell them the story of salvation and to involve them in this story” (Pope Benedict XVI, General Audience, November 18, 2009).

We will see in a moment just how important these stories and images are to understanding the full meaning of the windows, but first let us examine what was behind their ascent from modest functionality to sublime expression.

Structural Marvel

Fundamentally, a window is a hole punched in a wall. It represents a compromise between the structural integrity of the building and the occupants’ requirements for comfort. Punch too many holes and the walls will come tumbling down, too few and the interior will be dark and stuffy. Modern materials and construction techniques make almost any configuration of wall and window possible, but in the days of wood and stone and brick and mortar, the options were more limited.

To support heavy barrel-vaulted ceilings, for example, and to cope with the powerful lateral forces they generate, Romanesque church builders had to put up massive, fortress-like walls, and risk only sparsely-strewn and diminutive windows. That made for predictably gloomy interiors.

The pointed or Gothic arch, a 12th-century innovation, was game-changing. Compared to the older Roman form, it produced far less outward thrust, allowing Gothic masons to raise up taller and thinner walls. They took care of any residual stresses with another innovation: pillar-like buttresses, each acting like a narrow slice of Romanesque wall, offset from the main body of the church by an arched bridge or “flyer.” These and other engineering advances resulted in a slimmed-down structure that was essentially an airy skeleton of slender columns and ribbed vaults, “skinned” in between by lightweight, non-load-bearing materials—like glass.

Glass Bible

Windows, stained glass or otherwise, had been a grudging accommodation in Romanesque architecture; the Gothic arch embraced them and freed them to spread throughout the church in almost any size and configuration: galaxies of medallions, roundels, trefoils, and quatrefoils, traceried lancets (narrow arched windows), and breathtaking wheels and roses. They were the new glass pages of the “Poor Man’s Bible” of sacred imagery. Indeed, in a Gothic church, with virtually no continuous wall space for paintings, frescoes, or mosaics, they were the only surfaces on which such imagery could appear. Back-lit by the sun, they showed it off to better advantage, like giant flat-screen TVs or a kind of medieval JumboTron.

It would be endless and unnecessary to try to describe a window in all its pictorial details. For example, the swirl of light and color above the west portal at Chartres depicts Christ the Judge (in the center of the rose) orbited by three dozen roundels of the Evangelists, apostles, and elders of the Apocalypse, attended by angelic trumpeters calling the dead from their graves; the three lancets underneath lay out the genealogy of Jesus, alongside episodes from his life, beginning with the Annunciation and leading to the Resurrection.

But in a sense it hardly matters.

As worthwhile as it is, however suitable for catechesis and instruction, the pictorial content of stained glass windows, which by and large repeats familiar subjects and compositions from other art forms, only supplies the windows with their most obvious, literal level of meaning. Its connection to the glass (or to paint or any other medium) is accidental, not substantial, and the windows would be meaningful without any of it. After all, not a few of them are so small or intricate as to be illegible from any normal vantage point, and some are non-figurative, or decoratively patterned. Besides, even when the imagery is readable, contemporary viewers may be unacquainted with the symbolic and artistic conventions needed to interpret it (which is not to excuse ourselves from making the effort to become acquainted).

Nevertheless, physical features like the windows’ shape, number, and location may be more immediately accessible today than the obscure details of a medieval saint’s life.

Formal Reminder

It is not too difficult to recognize the circle as an emblem of eternity or divine perfection, for example; rose windows and linked roundels additionally express the interlocking order of the cosmos, centered on Christ. (Although some are devoted to Mary—the “Mystical Rose”—rose windows should not be reflexively associated with her, since they were not so called until the 17th century.) Trefoils allude to the Trinity, squares to the Evangelists or the four ancient elements. Mathematical harmonies like the golden ratio stand behind the pleasing proportions of many a Gothic window or arch. Other shapes and configurations hold their corresponding meanings.

As for location, in a cruciform church the ends of the nave and transepts are reserved for the most important or elaborate subjects, usually in rose windows. Lancets of saints typically line the nave and choir, a standing host of witnesses and role-models for the congregants below.

Not least, there is the windows’ dazzling beauty—“the splendor of the truth” speaking through the eyes to the heart and urging it along the via pulchritudinis (the way of beauty) to the Author of all beauty and all truth. All this is meaningful, but still none of it touches the windows’ defining trait and their deepest meaning: that they are the means by which light enters the church—which returns us to their practical uselessness. A Gothic interior remains a comparatively dim place, no matter how many windows it boasts. But while they could be improved upon as sources of illumination, ultimately what matters is not the quantity of light they admit, but what they do with it.

Boundary of the Invisible World

God is light (1 Jn 1:5), of course, a spiritual and intelligible light, a light that can be understood, a light that fills creation and gives life to our souls. Medieval theologians found a perfect analogy in visible light, especially in the superabundant radiation of the sun, which fills the material world and gives life to the assembled multitudes of stained glass, and filtering through them, the heart of the church as well.

The sun’s light itself is a living thing, active like the Holy Spirit, rhythmic like the liturgical seasons. Its various moods play over the face of the windows in a continuous drama of light and shadow. They may be ablaze with mid-morning cheer and hope, or subdued and contemplative with winter shadows. Sunrise and sunset will tinge them blood-red. At night they rest in penitential blackness, awaiting their morning resurrection. It is not insignificant that from outside the church they look deceptively bleak and impenetrable. Goethe observed (in “Poems are painted windows . . .”) that they appear “in darkness wrapped” to the “ignoramus” standing in the market-place; only from within the church are they “clear and bright” and “fraught with meaning to the sight.”

Time and the viewer’s position (and disposition) are thus bound up with the windows’ meaning. Add in their prismatic colors and their endless variety, and they become a model of the many pathways to God, the diverse channels for grace, that Catholicism generously affords the faithful.

Reformation iconoclasts in search of “biblical simplicity” found that rich diversity reason enough to smash many masterpieces of stained glass to bits. In Nathaniel Hawthorne’s The Marble Faun, a character unsympathetic to the Church, referring to the windows of St. Peter’s, contends that

[d]aylight, in its natural state, ought not to be admitted here. It should stream through a brilliant illusion of saints and hierarchies, and old scriptural images, and symbolized dogmas, purple, blue, golden, and a broad flame of scarlet. Then, it would be just such an illumination as the Catholic faith allows to its believers. But, give me—to live and die in—the pure, white light of heaven!

Progressive-minded Catholics similarly object that stained-glass windows are relics of the pre-Vatican II Church, literally closed to the “fresh breezes” of modernity.

The modern world has little patience for traditional art and symbols, and, often enough, for symbolism of any kind. Contemporary church design not infrequently succumbs to bottom-line thinking and minimalist aesthetics (and minimalist spirituality?). We expect well-lit interiors, so the subtle glow of stained glass gets sacrificed to the bleached “convenience” of flood lights. Ordinary windows are cheaper, but their transparency leaves both window and light unaltered, and therefore routinely unnoticed. Nothing prevents architects from doing wonderful things with the most ordinary materials, or us from assigning meaning to anything, even incandescent light bulbs and factory-made windowpanes. Clear glass vessels, which suffer no damage from the passage of light, reminded medieval Catholics of Mary’s spotless virginity. Nothing prevents us, except inattention and indifference.

No wonder then that we can overlook the most profound meaning of stained-glass windows: that each one is a shining symbol of the Incarnation. That is broadly true of all art, which plants the artist’s immaterial idea in a material body. But stained glass uniquely receives light, in itself invisible and intangible, and gives it a solid, visible form. Like Mary, each piece of glass is pregnant with light. And like Jesus, each makes known the hidden “father” of light, the sun, which subsists beyond the physical walls of the church, inaccessible to the bodily eye.
Stained-glass windows, of the Gothic or any era, may fail in the practical realm. But as symbols they stand at the boundary between the seen and the unseen, shining in the darkness with the glorious light of Christ, the light that is, in Eliot’s phrase, “the visible reminder of invisible Light” (“Choruses from The Rock”).

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