Every once in a while, an exhibition comes along that is so stunning, important, and well timed that it makes almost everything else on view seem trivial and beside the point.
One remembers the retrospectives of Matisse, Braque, and Miro of several decades ago; the shows of Rembrandt's etchings, Durer's engravings, and Holbein's drawings of more recent years; the exhibition of Cezanne's late work and the display of Picasso's lifetime production a few seasons back; and the magnificent Manet retrospective of last year.
To that list must now be added one more rare and beautiful event: the current Van Gogh exhibition at the Metropolitan Museum here. ''Van Gogh in Arles'' is a perfect gem of a show. Its 146 paintings and drawings represent the best of what Van Gogh produced during the 15-month period in 1888-89 when he stayed in the southern French town of Arles. Among them are a number of the very best works of art in the past century, including numerous drawings that evoke the draftsmanship and depth of Rembrandt, and several paintings of such awesome simplicity and originality that they can only be ''explained'' by declaring Van Gogh as being both a genius and great.
The show is organized chronologically, beginning with an introductory section devoted to the last months Van Gogh worked in Paris. From then on, the viewer moves with the artist as he meets the people of Arles and gets to know its buildings, nearby countryside, and communities a short distance away. The particular significance of the two-month period that Van Gogh and Gauguin lived and worked together is documented by several major examples of both artists' work. In addition, great care has been taken to bring together - for the first time since they left Van Gogh's studio - multiple versions of many key subjects, related studies and paintings, and groups of drawings that the artist sent to his brother, Theo, and to friends.
The result of all this care and planning on the part of Ronald Pickvance - who curated the exhibition in consultation with the museum's staff of the Department of European Paintings - is an artistic event that not only dramatically reaffirms Van Gogh's quality and importance, but is so perfectly realized that it will remain in the memory of those who participated for many years to come.
It is difficult for us today to understand why Van Gogh's accomplishments weren't immediately recognized. It seems so very obvious that his art was true, deeply felt, carefully thought out, and executed with great originality and depth. We all - art professionals and interested laymen alike - are touched by ''Van Gogh's Bedroom,'' ''The Night Cafe,'' ''Van Gogh's Chair,'' ''Portrait of Joseph Roulin,'' ''L'Arlesienne,'' and the hundreds of other paintings and drawings he produced during his incredibly short career. We cannot imagine how anyone, even during the time of the French Academy and its narrow restrictions, could have failed to detect their remarkable quality, their greatness.
And yet, a moment's thought will provide the answer. Van Gogh was too forceful and direct, too concerned with the essential form and truth of what he encountered, and too involved with translating his perceptual experience into the most perfect combination of line, mass, and color to concern himself with viewing life or art in a secondhand, prepackaged, or orthodox manner.
Painting in his day viewed reality through the thick, heavily encrusted lens of a centuries-old tradition, or through the shallow lens of fashion. It simply wasn't ready - despite Impressionism's dents upon the Academy - for the blunt, no-frills approach of Van Gogh. Unlike his academic contemporaries, Van Gogh addressed life directly through his art, and in the simplest, most immediate manner possible. He confronted reality head-on, but with method and knowledge, and his style was a direct expression of that confrontation, not a tradition or fashion-bound device designed carefully to dole out only what was culturally acceptable.
The miracle is how wondrously on target, how right, he almost always was when doing something new and different. His ability to turn a very ordinary cornfield or a pair of shows into a work of art that both quivers with life and becomes virtually an icon representing the true, the totally unique characteristics of the place or object depicted, was uncanny. But just as amazing is the fact that what he produced should become such a fountain of inspiration for future generations of artists and anyone else the least sensitive to art.
Van Gogh was not a mad genius daubing paint onto canvas in a frenzy of irrationality, but a profoundly feeling, deeply concerned, and highly intelligent artist who devoted his last years to transcribing his deepest perceptions of truth into images on canvas and paper. The price he paid for his passion and integrity was formidable, but he paid it. After all, he really had no choice.
There are ultimately no words to describe adequately the rare beauty of this man's art, its simple, singing truthfulness, or its richly imaginative use of color and line. It must be seen to be fully grasped, and for that we are extremely fortunate to have this show.
''Van Gogh in Arles'' will remain on view through Dec. 30. Admission is by ticket only - which can be purchased at the Metropolitan, or through Ticketron and Tele-Tron outlets throughout the United States.