How do you see something that’s not there? It’s a question that Bill Viola, one of the world’s leading video artists, frequently poses. For more than four decades his experimental works have been exhibited in museums and public spaces around the world, many commissioned by institutions like the Guggenheim, the Whitney, and the Museum of Modern Art in New York City, others by the International Olympic Committee in Athens, St. Paul’s Cathedral in London, and the Doha International Airport in Qatar.

But the pivotal moment in Viola’s career took place in much humbler surroundings. It was 1991, not long after his mother’s death, and he was removing a few objects from the kitchen cupboard. Taking down a small green-and-white bowl, originally a gift from his mother, Viola recalls being flooded with memories and emotions, returning him to the moment when he first received it:

I could feel [my mother’s] hand and see her face, vividly, as she handed it to me that day. At that point, my relationship to material objects changed—completely and irrevocably. . . . After that I looked around and realized that all of the things I was encountering were like this. They each contain the presences and desires of their makers.

For Viola, the otherwise empty bowl becomes a node of connection, charged with the invisible presence of his mother. A similar dynamic informs his video art: moving images, by definition fleeting, intangible, and impermanent, can nevertheless serve as portals into sacred realities that transcend space and time.

While it’s not a full-scale retrospective, I Do Not Know What It Is I Am Like: The Art of Bill Viola, on view at the Barnes Foundation in Philadelphia through September 15, transports audiences to the heart of the artist’s pioneering inquiries into the phenomenon of visual perception. Curated by longtime admirer John Hanhardt (who commissioned many of  Viola’s works, organized prior shows, and wrote a monograph), it’s the first-ever exhibition devoted to video art at the Barnes. Such a setting harmonizes well with Viola’s practice and sensibility, which are formally innovative yet thematically rooted in the European art-historical tradition: just as the Barnes houses classic European paintings within a sleek modern space, so too do Viola’s cutting-edge video installations feature imagery inspired by old masters like Giotto, Jacopo da Pontormo, and Albrecht Dürer. Rather than a chronological survey, the show has the feel of a meditative essay, encouraging visitors to make connections between the works (there are eight on display, their glowing screens spread across five darkened galleries) and spend time pondering the spiritual and theological mysteries evoked by Viola’s art.

Viola’s film I Do Not Know What It Is I Am Like (1986), its title a loose translation of a Sanskrit verse from the Rig-Veda, serves as the intellectual and spiritual touchstone of the exhibit. Eighty-nine minutes long, it unfolds as a wordless odyssey, an epic quest for self-understanding and transcendence that ranges from mountain lakes and underground caves to grassy fields and remote islands. Viola contemplates the cryptic gazes of wild animals (mostly fish and birds, but also a pair of bison, a zebra, and an elephant); takes us inside his studio (playfully modeled on seventeenth-century Dutch still-lifes); leads us through an intense, violent sequence filled with split-second flashes of lightning, crowded highways, and roaring flames; then drops us down in the middle of a raucous firewalking ritual in Fiji, the soundtrack filled with beating drums and wailing wind instruments. The film concludes in a forest, close to the lake where we began.

These different settings, and their varied imagery, may seem disconnected, but in fact they’re all one, intertwined like threads of a tapestry. It’s the medium of video that enables us to perceive their unity, as the camera’s capacity to compress and extend time (by speeding up and slowing down), and to grow and shrink the visual field (by zooming in and out), mimics the workings of the human mind. Like the faculty of memory, the process of editing and combining video footage, and viewing video art, helps us see what we ordinarily can’t, as, in Viola’s words, the “diverse forms of nature continue to reveal their common origins”: 

 . . . .there is a single moment when the flash of insight bursts into your unguarded mind, when all the pieces fall together, when the pattern is seen or the individual elements uncovered . . . when the breath of clarity opens the mind and you “see” for the first time in a long while, remembering what it was like again as if suddenly jolted from sleep.

Indeed, the film has the uncanny feeling of a dream, conveying an intimate knowledge whose truth lies beyond the range of ordinary speech. As Viola’s images accumulate (water dripping from stalactites, flies buzzing around a decomposing fish, a snail sliding across a table, a chick hatching from an egg) they begin to converge and illuminate one another, revealing the elemental and opposed forces of creation and destruction constantly at work in nature—and, by extension, in ourselves.

Yet as much as Viola celebrates the power of images to reveal connections, he also leaves room for mystery. Human beings, as the world’s great religious traditions contend, are both part of the natural world and uniquely separate from it, an idea Viola dramatizes in one of the work’s most compelling sequences. He films a horned owl at medium distance, slowly and steadily zooming as the animal gazes directly into the camera. After about two minutes, we begin to discern Viola’s reflection mirrored on the surface of the owl’s enormous eye. Viola then cuts abruptly to a close-up of the owl’s black pupil, ringed like an icon by its gold cornea, as Viola moves within it. Here Viola’s attempt to penetrate the owl’s inner world is blocked by his own reflected image. His search for self-understanding fails, yielding not the illumination of wisdom but instead an awareness of what he terms “the irreconcilable otherness of an intelligence ordered around a world we can share in body but not in mind.”

Darkness and defeat, of course, aren’t necessarily negative. As the Christian mystics remind us, they’re crucial stages in the soul’s journey to God. Recall the Dark Night of the Soul, a short text by the sixteenth-century Spanish Carmelite St. John of the Cross. Viola became fascinated with the poem in college, later turning its paradoxical imagery (night shining like sunrise, oblivion yielding knowledge) into a video installation in 1983. (Entitled Room for St. John of the Cross, it’s unfortunately not on view at the Barnes.) Similarly, Viola draws on The Cloud of Unknowing, a fourteenth-century treatise on contemplative prayer by an anonymous English monk, for  Pneuma (1994), in which staticky black-and-white projections mimic the way unbidden memories float in and out of consciousness during meditation.

The moment of mystical union, when the self ecstatically bursts from its limits and becomes one with something larger, likewise informs Viola’s 1976 installation He Weeps for You, whose title alludes to the idea of self-sacrifice found in the Bible. Here a closed-circuit camera films viewers from behind a dripping copper spigot. As they enter the gallery, a projector casts their zoomed image, contained within a steadily growing drop of water, onto a large screen. The drop swells before finally falling onto an amplified drum below, the booming sound echoing throughout the gallery. The process, where a tiny drop is suddenly converted into sound waves that fill an entire room, encourages viewers to ponder the ways in which the microcosm of the self—small, contained, limited—mirrors and is in fact one with the macrocosm that surrounds it.

In the second half of his career, beginning in the mid-1990s, Viola turned his attention from nature and the language of religious mysticism decisively toward the human body. Concerned about the ways his chosen medium of video was increasingly exploited for distraction, fragmentation, and manipulation in the dawning digital era, Viola began studying the perspectival theories of the Italian Renaissance. Paintings by figures like Giotto (Viola was struck in particular by his St. Francis Receiving the Stigmata in the Louvre) display a spiritual sincerity and an abiding trust in the world as it appears; not only is it observable, and thus knowable, it’s also linked to the world we can’t see, as human figures and the spaces they inhabit become windows into the divine.

The Barnes show devotes a gallery to four works from this period. It’s like entering the European painting wing at the Met, except that the images are moving. Close to the entrance is Ablutions (2005), a diptych in which two nude male and female torsos reverently approach two streams of water before dipping their hands to produce a slow-motion splash. On the opposite wall is Observance (2002), in which a long line of men and women file up to and peer out from the screen, their faces contorted in grief as they witness an unseen horror (they’re modeled on Dürer’s Four Apostles from 1526). The prayerful tone is deepened by Catherine’s Room (2001), inspired by a fourteenth-century predella by Andrea di Bartolo featuring five scenes from the life of St. Catherine of Siena.

But the focal point is The Greeting (1995), a massive installation that transforms a single moment from Pontormo’s Visitation (1529), in which a pregnant Mary greets Elizabeth, into a long slow-motion scene that plays out over the course of ten minutes. We witness every minor change in facial expression, every unconscious gesture, every shifting fold of clothing as the two come together and embrace at the center of the nine-by-seven-foot screen. Though Viola removes the Christian framing of Luke’s gospel (these could be any two women, not necessarily Mary and Elizabeth) and invests the scene with considerable ambiguity (a third woman arrives, but her presence is never explained), the work nevertheless conveys a moment of profound hope, even joy, as a fleeting moment of friendly recognition is extended in time, becoming almost permanent.

As a video artist, Viola knows that his works can only gesture at permanence. His medium, he insists, is not light, or motion, but time. And though it can be said his videos “cease to exist” each night when the museum closes and shuts off the power, still they manage to convey a sense of the eternal. Nowhere is the enigmatic relationship between time and timelessness more powerfully on display that in Ascension (2000), which occupies its own gallery. Over ten minutes, we watch as a fully clothed man plunges feet-first beneath the surface of dark blue water, his cruciform body surrounded by a cloud of bubbles as he first sinks, then rises, and sinks again. Here Viola symbolically evokes the self-emptying paradox (kenosis) at the heart of Christianity: the ever-living God freely becomes mortal, diving down (in the person of Christ) into a broken world of temporality and death, giving his life in order to rescue fallen humanity, leading them back to eternity.

Taken together, Viola’s works in video show that screens, as much as they can distract, even enslave us, need not be superficial. Certainly, video can be cynically put to dark purposes (think of “deepfakes” and internet memes), but it can also bring us into contact with deeper realities, enhancing our propensity for connection and compassion. There’s a poignant image Viola uses to describe human life in the age of media hyper-saturation—the Buddhist Bodhisattva Avalokiteshvara, also known as the God of Compassion:

He has a thousand arms to reach out and touch all the suffering beings in the world, and a thousand eyes. . . . We see [him] depicted with a tower of heads stacked on top of each other on his shoulders in order to look out in all directions.

That image, of course, is all of us, with our smartphones, computers, TVs, and tablets. We can see into corners of the world we never could before—and therefore, Viola argues, we now hold the capacity (and the responsibility) to offer comfort and consolation to each and every suffering person who inhabits it.