"Let there be light," sang the University of Maryland Chorus last night. And there was light, as written into the music of Haydn's "The Creation," a burst of radiant harmony in the orchestra.

There was even more radiance in the chorus throughout the evening--purity and richness of tone, delicacy of balance, alertness of rhythm and superb clarity of diction.

Music director Paul Traver and his chorus were celebrating two anniversaries with their performance of "The Creation" in the Kennedy Center Concert Hall: Traver's 25th aniversary on the Maryland faculty and the 15th anniversary of his founding of the chorus. No observance could have been more appropriate than their joyful, exquisitely polished performance of Haydn's masterpiece.

If there is any problem in "The Creation," it is a problem of constant positive thinking--exactly the opposite of the problem posed in Haydn's "Seven Last Words of Christ," where he had to compose a long, unrelieved series of mournful slow movements. Even the primordial chaos with which he begins seems to be a rather tidy, 18th-century sort of chaos, nothing to compare with what we have been hearing in the decades since "The Rite of Spring" showed composers how to be really chaotic.

Haydn does have a storm, with thunder and hailstones, but it is over almost as soon as it begins, and it is followed by "the light and flaky snow," with an appropriately light and flaky melody. Lions roar in the music, a tiger pounces and insects buzz during the creation of living things, but these are colorful details with no overtones of threat. We are, after all, in the Garden of Eden, and the curtain falls on the story (which is drawn from the Book of Genesis and Milton's "Paradise Lost") just as Adam and Eve may be on the brink of going apple-picking.

This kind of material is harder to handle effectively than doom and gloom; everybody knows Dante's "Inferno," but few have worked their way through the "Paradiso," because things going wrong make more interesting art than things going right. Haydn's genius is nowhere shown more effectively than in his ability to make interesting art out of almost unrelieved joy and wonder. His final years, which produced "The Creation" along with dozens of other masterpieces, were among the happiest in the history of music, and he shared that happiness generously with his audience.

Traver and his chorus helped enormously in that sharing, and they were greatly aided by three soloists of the highest caliber: soprano Linda Mabbs, wonderfully light and agile; tenor George Shirley, rich in tone and dramatic in style; and bass Donald Gramm, as always, a master in the expressive use of words, subtleties of phrasing and fine nuances of vocal color. The orchestra had a few small lapses in its ensemble playing, but it included some of Washington's best musicians. Two of them, harpsichordist James Weaver and cellist Kenneth Slowik, were asked to take special bows at the end, and they were richly deserved.

But most of the tumultuous applause was reserved for Traver, who has been earning it for a quarter of a century--most particularly in the 15 years he has been leading this remarkable chorus.