On September 24, 1845, John Ruskin wrote an unguardedly rapturous letter to his father from Venice, describing the momentous impact onhim of the paintings he had seen earlier that day by Jacopo Tintoretto, at the Scuola di San Rocco:

I have had a draught of pictures today enough to drown me. I never was so utterly crushed to the earth before any human intellect as I was today, before Tintoret. Just be so good as to take my list of painters, & put him in the school of Art at the top, top, top of everything, with a great big black line underneath him to stop him off from everybody–and put him in the school of Intellect, next after Michael Angelo. He took it so entirely out of me today that I could do nothing at last but lie on a bench & laugh…. M Angelo himself cannot hurl figures into space as he does, nor did M Angelo ever paint space itself which would not look like a nutshell beside Tintoret’s.

Tintoretto is hardly a household name, and it certainly holds little of the aura that Ruskin’s effusive language implies, especially not in comparison with that of Michelangelo. Part of the reason is that most of Tintoretto’s work is permanently installed on the walls and ceilings of Venice, where the artist spent his entire life. That is why no one would have been able to form much of a picture of his staggering artistic achievement unless they had spent some time in Venice. “I had always thought him a good & clever & forcible painter,” Ruskin wrote, “but I had not the smallest notion of his enormous powers…. It is marvelously lucky I came here, or I might have disgraced myself for ever by speaking slightly of Tintoret. I look upon him now, though as a less perfect painter, yet as a far greater man than Titian.” But Titian and Michelangelo, along with Leonardo and Raphael, are widely considered the first-magnitude stars of Italian art. Who other than Ruskin would have placed Tintoretto among or even above them?

One difficulty is that Tintoretto has no pivotal place in the grand art-historical narratives most of us carry with us when we visit museums. He was, unlike his fellow Venetian, Titian, not really part of the Renaissance; he belonged instead to the Mannerist era–a period still dimly understood–that came just after it, and that Tintoretto helped shape. Consider, for example, the Annunciation in San Rocco, which especially moved Ruskin. In Renaissance painting, the annunciate Virgin is depicted as receiving in sweet resignation the news of her tremendous fate, from an angel who acknowledges her purity by kneeling in her presence. That is how Fra Angelico, for example, painted the hushed scene. Tintoretto’s, by contrast, is pure noisy wildness, as the angel sweeps into the Virgin’s space with the force and clatter of a compact tornado. Ruskin’s description matches its intensity:

Not in the meek reception of the adoring messenger, but startled by the rush of his horizontal and rattling wings, the Virgin sits…not by the green pasture of the restored soul, but houseless, under the shelter of a palace vestibule ruined and abandoned, with the noise of the axe and the hammer in her ears, and the tumult of a city round about her desolation.

Nothing in Renaissance art would have prepared anyone for a work like this. No one in Italy would have imagined setting Mary in the midst of an urban ruin, of exposed brick and crumbling stucco, emblematizing a fallen world, with the messenger implicitly having to shout his message in order to be heard above the ruckus of his entry. Work after work in Tintoretto’s decorative program for the Scuola, which bears comparison in every respect with that of Michelangelo’s Sistine Chapel, reinvents and refreshes stories that everyone in Venice knew, crowding them with details that amplify the joys and sufferings that had perhaps lost their edge through over-representation. Ruskin draws attention to the presence, within sight of the agony on the cross, of “an ass in the distance, feeding on the remains of strewed palm leaves.” When Auden wrote “About suffering they were never wrong,/The Old Masters,” he was thinking of the Mannerists.

Tintoretto addresses each motif as if it had never been painted before. Yet for all his inventiveness, his unbridled fantasy and the fierce energy of his execution, he does not really anticipate the Baroque style, which emerged after his death. His work has an eccentricity and the arcane sophistication that is the signature of Mannerism. The purpose of Baroque was to restore faith and counter the Reformation. None of that belonged to the Mannerist agenda.

All this may help explain why there has not been a monograph exhibition of Tintoretto’s work since 1937, held at the Palazzo Pasaro in Venice–the one city in the world that has no need for such a show, because of its near monopoly of his prodigious output. A show of his work elsewhere seemed neither practical nor imperative. So the kind of experience Ruskin underwent has been among the unanticipated rewards of a trip to Venice. One of the main contributions of the inspired exhibition of his work at the Museo del Prado in Madrid (until May 13) is that it makes it clear that Tintoretto really is as exciting as Ruskin made him sound. It is a beautiful and unforgettable show, and a reason to visit Madrid this spring, in case you needed a reason.

The exhibition is installed in the long central gallery of the Prado’s upper floor, temporarily divided into a succession of spaces, each given over to a stage in the artist’s unfolding career. It is not a dauntingly large show but a selective one, with each painting given enough space so that one can, without exhaustion, look deeply at the work in each of the galleries. Just before entering the first of the spaces, we are confronted by a small, intense self-portrait of Tintoretto as a young man, in which the artist turns his head toward us. He looks as if distracted from a dream by our presence. In truth, of course, Tintoretto would have been studying his own features when he painted it, and there would have been no room in his field of sight for anything but himself. We thus see him as he saw himself, putting us inside and outside his gaze at once–so when we round the wall and enter the first gallery behind it, it is like entering into the artist’s mind and occupying his vision from within.

The first work we encounter, on the wall that faces us once inside, is itself like a dream. It shows Christ Among the Doctors–a picture in which ponderous books are being opened and pored over, as scholars hunt down the passages the youthful Jesus cites. It is a typical Mannerist composition in that the central figure–Jesus–is seated, almost enthroned, in the far distance, discoursing animatedly, sending the doctors back to their heavy volumes to check his references. They look over one another’s shoulders, pointing in excitement to this or that text. Jesus has caused, through his rabbinical erudition, an almost hallucinatory scene of bibliomania. The adolescent prophet displays knowledge beyond that commanded by the bearded Michelangelesque pundits. Whole choruses of readers spill up and down the stairs that lead up and back to Jesus, distinguished by a halo too big for his youthful head, and fill the podiums on either side of his chair. A woman standing at the left surveys the unbecoming tumult, and the whole scene is energized by Tintoretto’s typical raw and urgent brushwork, which initially put off his critics, who demanded greater finish.

Here, for example, is his Florentine contemporary Giorgio Vasari on Tintoretto’s Last Judgment:

As to the matter of painting, he may be said to possess the most singular, capricious, and determined hand, with the boldest, most extravagant, and obstinate brain, that has ever yet belonged to the domain of that art. Of this there is sufficient proof in his works, and in the fantastic composition of his stories, which are altogether different from and contrary to the usages of other painters; nay, he has been more extravagant in some of his more recent inventions, and in those strange caprices of his fancy, which he has executed almost by hap-hazard and without design; insomuch that one might suppose, he well nigh desired to show that the art is but a jest.

One is shocked to find so early an accusation that a piece of art must be a joke. The operative word is “design” (disegno), which was the mark of Florentine probity in painting. Since Vasari, an upholder of Florentine aesthetics, finds it lacking everywhere in Tintoretto, he cannot take this painting seriously. But it is inconceivable that an Italian artist of the era could have painted so “fearful and terrible” a subject, as Vasari described it, in jest. The likelier explanation is that Vasari was applying critical criteria appropriate to a style of painting that Tintoretto had already gone beyond. One of our own contemporaries has described him as a “slow starter,” but Christ Among the Doctors, painted around 1542, when Tintoretto was still in his 20s, had broken new artistic ground as part of a convulsion that was sweeping the European vanguard, from Bruegel, Cranach and Drer in the north to El Greco, late Raphael and Michelangelo, Pontormo and Bronzino in the south. It is to Ruskin’s credit that he caught on instantly, though Mannerism had not yet been identified by art historians:

Away he goes, heaping host on host, multitudes that no man can number–never pausing, never repeating himself–clouds & whirlwinds & fire & infinity of earth & sea, all alike to him–and then the noble fellow has put in Titian, on horseback at one side of one of his great pictures, and himself at the other.

In the same gallery as Christ Among the Doctors is Conversion of Saint Paul, which exemplifies the spirit that Ruskin succeeds in capturing. “Tintoretto raises the high drama of the episode to the level of pandemonium,” the catalogue entry reads, and one has the distinct impression that not only Paul but the world itself has been convulsed, with riders flung from their horses in every direction and the riderless horses sent flailing in surging waters, as Jesus opens the heavens and a single horseman gallops over a bridge and out of the picture under a fluttering pink banner, bearing the news to mankind. Paul, under the physical impact of his vision, lies writhing, like Laocon, amid stones on the ground, picked out by the uncanny light. There were many picturings of Paul’s conversion in the Renaissance, but Tintoretto translated inner turbulence into external chaos, much as he had externalized Mary’s trepidations as the shattering of reality itself.

As for pictorial jokes, the show has several of them, but we always know when we are looking at one, as in the raunchy Venus and Mars Surprised by Vulcan. Venus lies demurely in the love-tossed bedsheets, as her entirely unsuitable husband, Vulcan, lifts one of the corners, as if performing a gynecological inspection. The sight of his wife’s sex distracts him from the yipping of a tiny spaniel, barking at Mars, hiding under another bed, who must have worn his helmet even when making love. Venus’s child, Eros, snoozes through the chaos, holding a clutch of arrows. A slyer, subtler joke by far animates Saint George, Saint Louis, and the Princess. In the canonical representation of Saint George, he is shown, mounted and armored, slaying the dragon that terrorized a community that was required to sacrifice its members to the monster’s appetite. The saint appeared just in time to rescue the princess, whose turn it was to be eaten. There is in fact a wonderful painting in this show of this mythical triangle, in which the male protects the female from the monster. In the present painting, however, which has the edginess of a feminist joke, the princess has taken matters into her own hands. She is shown, with the dragon between her legs, gazing at her own lovely likeness in Saint George’s polished armor. The dragon lashes his scaly tail in pleasure as the princess rests one hand on its wing, holding a crop with the other. George spreads his arms in a gesture of male helplessness, as his lance lies broken on the ground. The princess and the dragon seem entirely happy with the arrangement, while Saint Louis casts his eyes demurely down at the shattered weapon and the smug reptile. It was obviously painted with a sophisticated Venetian audience in mind.

But Mannerism’s audience was sophisticated: It got the point, and the paintings are planted with clues that flattered its cognitive prowess. We, as part of that audience, know things to which the personages in the painting are blind, and comedy and tragedy get mixed. Judas sits at the table in two of the Last Suppers, his back to us, hiding a sack of coins behind him. Nobody seated at the table–only we outside the picture–is aware that he has been bribed. In the great Susannah and the Elders, the outstanding painting in the show, beautiful Susannah sits nude in the garden, gazing deeply at her image in the mirror propped up in front of her, while the whiskered elders, peering from both sides of a hedge of roses, gaze at her lush nakedness. We, hypocrite viewers, gaze at the gazers, condemning the prurient elders while relishing what they ravish with their eyes–until, in a sudden onset of consciousness, we realize that we have been trapped by the same delicious vision, enjoying what we condemn them for enjoying. Ruskin’s inclination to laugh was a visceral tribute not to humor but delight at the effortless excess of power and mastery, of impulse and improvisation, and the scintillation of Tintoretto’s pictorial invention. There is no artist like him!