When Jacob Kainen, the Washington painter, married his wife Ruth in 1969, he rose to propose a toast to a friend he'd never met, Ernst Ludwig Kirchner, the German Expressionist master, then 41 years dead.

Kirchner died in misery, a broken man, a suicide. But one would not guess his grief from the 23 rare Kirchners in "German Expressionist Prints From the Collection of Ruth and Jacob Kainen," opening this morning at the National Gallery of Art.

The word "Expressionism" nowadays connotes an art of nightmare, of howling dogs and darkness, anxiety and rage. But the Kirchners here make war on gloom. They are prints alive with color, exuberance and music. Soft clouds float in summer skies, dancers twirl and bathers splash. "Expressionism began in gladness," Kainen says. This show contains much joy. Behind it lies a story of romance, collegiality, and prophecies fulfilled.

The Kainens owe to Kirchner an odd and touching debt. It was Kirchner, or his shade, who introduced them in 1968, during a luncheon at the Women's National Democratic Club. "We'd been seated next to one another," Ruth Kainen remembers. "Someone mentioned Kirchner, and Jacob turned, politely, to tell me who he was. I responded, with a little annoyance, that I had a Kirchner lithograph hanging on my wall. Two days later Jacob called to ask if he could come to see it. And we were on."

Their encouraging exhibition corrects an old imbalance. The vigorous, exultant graphics of the Germans are underrepresented in the art museums of this calm-approving city. The show reminds us, too, that Washington has long been a town in love with prints and that it was Jacob Kainen, in his guises as teacher and museum man, connoisseur and scholar, who helped to make it so.

Kainen, 75, is what J. Carter Brown, the gallery's director, calls "a triple threat: a curator, a collector and an artist all in one."

Kainen is as well a marvelous rememberer. As a "poor and footloose" painter in the early 1930s, he wandered through Manhattan's streets with his friend, Arshile Gorky. In all-night cafeterias, at openings, at parties, and in the busy graphic workshops of the Federal Arts Project, he met many of the most advanced artists of the day. Even then he was collecting, "but not collecting seriously. Pictures just adhered." He received his first two Gorkys "in exchange for posing." His first Stuart Davis print, a present from the artist, entered Kainen's small collection in 1938.

It was even harder then than now to make a living painting. Kainen came to sleepy Washington in 1942 to work as a curator in the Smithsonian Institution's Division of Graphic Arts. Armed for the first time with institutional funds, the young curator began buying art in earnest. He carefully inspected thousands of impressions. He met hundreds of art dealers. "They beat a path to my door. I had Smithsonian money, I bought." The huge collection he assembled shows what Joshua C. Taylor, the late director of the National Collection of Fine Arts, called "an extraordinary subtlety and catholicity of taste."

While buying prints by the Americans for that national museum, Kainen was collecting the Germans for himself. "I was a government employe, I had children to support, but still I used to set aside money for collecting. I knew the German Expressionists were greatly undervalued."

Both Kainens sensed correctly, long before the market did, that that was sure to change.

In 1964, Ruth Kainen bought an early Kirchner lithograph, "Girl in a Bathtub" (1908), for $395. In 1981, another Kirchner lithograph sold at public auction for $135,894.

That recent rise in prices surely is connected to the Expressionist revivial of the 1980s. But Jacob Kainen bought the Germans because he understood precisely how much their verve, their passion and their concern for the common man had given to the painters of the New York School. After all, he'd been there. As a young man in the 1930s, he had watched Milton Avery, Adolph Gottlieb and Mark Rothko scrutinizing German prints at J.B. Neumann's gallery in downtown Manhattan. "No one gives the Germans credit," Kainen says. But he had felt those objects influence the prints he'd made himself.

"German Expressionist prints were somehow related to the whole Depression period," he says. "We were doing street scenes, too, lonely streets and tenements. And the Germans spoke to us as they still speak to New Yorkers. Expressionism is big city art."

Long before her marriage, despite the cool restraint then so much in vogue, Ruth Kainen, too, had come to love -- and buy -- the Germans' wild art. She had a bit of money (she is a partner in a family firm, the Roseboro Lumber Co. of Oregon). And she had allies, too, many of them dealers (among them Harry Lunn, Jem Hom, Franz Bader and Sidney Mickelson of Washington). She thanks them one by one in her refreshingly direct essay on collecting included in the catalogue.

After 1969, the Kainens bought together. The 90 prints on view, Ruth Kainen writes, "come from three distinct collections which we sometimes refer to as His, Hers and Ours."

Andrew Robison, the senior curator in charge of the gallery's department of prints and drawings, encouraged their collecting. "Shortly after he came to the National Gallery of Art in 1973," writes Ruth Kainen, "Andrew Robison visited us. He was so enthusiastic about our German prints and drawings -- in 1976 he borrowed them for a period of careful study -- that I came to look forward to sharing each new acquisition with him. His appreciation seemed to give new purpose to our endeavor, and it suggested an easy solution to a problem that had come to trouble us: What was to become of the large body of material that was gathering."

The national museums here have often been attacked for their disdain for mere locals, but Robison has forged strong ties with Washington's collectors. It was he who asked Lionel Epstein, who collects Edvard Munch, to serve as a guest curator of the gallery's Munch exhibit. Later he invited Ruth Benedict of the Washington Print Club to search through the gallery's collections and pick the shadowed works displayed there in her "Night Prints" show.

And he has been rewarded. Benedict has given a number of prints to the gallery. Some of Epstein's superb Munches will end up there as well. And so will all the graphics in the present show. When the exhibition closes, they will remain there for study. One -- "Five Tarts," a Kirchner woodcut of 1914 -- was presented by the Kainens to the gallery on Friday. And the other 89 are designated gifts.

The Kainens' exhibition is admirably varied. It includes etchings, lithographs and woodcuts, impressions moody and exultant by artists famous and unknown. Some of them were printed on absorbent blotting paper, some on glossy surfaces. One by Christian Rohlfs (1849-1938), the grand old man included, is a curious little woodcut of 1921 done in purple ink on a bit of cloth. Unlike many newer prints from Paris and New York -- which have the cold, dead look of mechanical reproductions -- each of these acknowledges the process of its making. Here the plate was smudged, there the block was gouged. In almost every picture, one feels the still-warm traces of the artist's hand.

How these Germans loved to play with inks and plates and papers. The Expressionists of Germany began to work together in 1905 when four of them, in Dresden, formed a group called Die Bru cke (the Bridge). Its founders -- Kirchner, Fritz Bleyl, Erich Heckel and Karl Schmidt-Rottluff -- were architecture students in their early twenties. They loved the lusty and the fresh, abhorred the overcautious and refused to heed old rules.

The seeds of their revolt had been planted in 1900 when Kirchner saw an exhibition by the Munich Successionists. "Indoors," as he put it later, "hung those anemic, bloodless, lifeless studio daubs and outside life, noisy and colorful, pulsated in the sun." Appalled, he "had the audacious idea of renewing German art."

The first room of the show includes Kirchner's circus scenes and landcapes, his portraits and his fantasies. They date from 1905 to 1933. Some are bright-and-bold, some gray. No two are alike. An insistence on the fresh, a hatred of the stiff, glows in all his art. He was enormously prolific. Jacob Kainen points out that Kirchner managed to produce 2,150 prints, "a stupendous body of work unmatched by that of any other western printmaker, including Picasso, who outlived Kirchner by 34 years."

The second room is given to other artists of Die Bru cke, among them Otto Mueller, Max Pechstein, Heckel and Schmidt-Rottluff -- and especially Emil Nolde. Its most impressive images are Nolde's "Man in a Top Hat," a dark and ghostly lithograph of 1911, and a fine pair of his Hamburg harbor scenes, one gray with morning mist, one drenched with driving rain, both made the year before. Expressionism is frequently described as an art of social comment. But the landscapes and the seascapes here nearly steal the show.

The third room is devoted to German printmaking of the early 1920s. It is here one starts to feel the hopelessness and horror bred by World War I. Images of death abound, the crippled limp and grin, "The Prisoner" by Rohlfs stares coldly from his cage. This gallery includes two terrifying images by Walter Gramatte' (1897-1929), "The Great Anxiety" and "The Fall Into Infinity" (both 1918). Darkness here descends on the Kainens' exhibition. Its early joy, by now, has succumbed to gloom.

In the last room of the show, among its prints by younger artists, one begins to feel the presence of a new, sarcastic meanness. Old griefs have contracted into hardness and disgust. The "Lady in a Feathered Hat" in a lithograph by Otto Dix of 1923, despite her plumes and furs, has the hollow eyes and fleshless mouth of a living corpse. Comparably hideous is the thick-necked, thick-fleshed "Woman at Her Toilet," a Paul Kleinschmidt drypoint also of 1923. Rene' Beeh views his countrymen less with pity than revulsion, and the little-known Paul Gangolf, despite the power of his lithographs, fills his city scenes with hate.

Beyond the heartfelt passions that surge throughout this show, beyond its early gladness and its later mirthless laughter, another presence hovers, one calmer and more classical. It is the quiet spirit of Jacob Kainen's recent art.

The Expressionists he collects concerned themselves with joy and grief, with anger, lust and savagery. But Kainen's abstract paintings spread a balm of peace. The Jacob Kainen who so deeply loves the agitated, seething prints of the Expressionists, and the Jacob Kainen who paints images of classical serenity, seem two different men.

In the 1930s he portrayed the lonely unemployed wandering the streets. Now rectangles of color float within his oils. His graphics in the '30s hymned the victims of the Dust Bowl and the Spanish Civil War. Now his costly objects are handsomely displayed in the marble halls of the National Gallery of Art. He pauses for a moment, and ponders without smiling, before trying to resolve what might seem contradictions.

"Every artist has both an expressionist and a classical side if he has any depth as a person," says Kainen. "Think of Picasso -- doing these beautiful, classical drawings at the same time he was doing these wild paintings. Goya did graceful portraits while at the same time he showed Saturn devouring his children. Sometimes you feel serene, sometimes agitated . . ."

He paused again. "How can I explain it? I think classicism works better in painting than in print-making. The print gets its character from its physical quality . . . You may not know my paintings of the 1930s and the '40s. I had 30 years of Expressionism. Then in the 1950s, during the McCarthy time, I lost my image. My art became absract. I became disillusioned with the common man . . . "

But he is not disillusioned with museums or art history, print-making or pictures. What has never wavered is his connectedness with art. The Kainens' exhibition is a sign of that commitment. On view in the East Building, it will close on Feb. 9.