NEW YORK PHILHARMONIC. Memorial concert benefiting the World Trade Center disaster relief fund. Brahms' "German Requiem." Heidi Grant Murphy, soprano, Thomas Hampson, baritone, Kurt Masur, conductor. With the American Boychoir and the New York Choral Artists. Thursday night. Avery Fisher Hall, Lincoln Center. The event, telecast "Live From Lincoln Center," will be rebroadcast tonight at 9 on WNET/13.

THERE ARE MOMENTS when classical music, by common consent, ceases to be a marginal form of entertainment or the finicky preoccupation of the affluent and few, and becomes an essential source of nourishment. Or perhaps that is wishful thinking: Music now also seems more than ever beside the point, requiring an intensity of focus that few of us can muster. Our attention spans, never long to begin with, have been fractured, our thoughts crowded with looped images of ash and flame and plummeting steel. What room is there for art?

Yet for a beautiful hour Thursday night, Avery Fisher Hall became a haven of concentration. In lieu of a festive opening night gala, the New York Philharmonic offered a benefit performance of Brahms' "Ein Deutsches Requiem" as a balm, and it was reverently accepted. All the signs of distraction that usually accompany a concert here - muttering, shuffling, coughing and snoring - had vanished. Aside from one stray cell phone early on, an attentive silence reigned. At the end of the performance, by request of the orchestra's executive director, Zarin Mehta, the audience held its applause and filed out of the hall in silence, letting the music hang in the air for a few extra minutes.

Had the Philharmonic chosen only to remember the dead, it might have played a program of threnodies, beginning, perhaps with Richard Strauss' "Metamorphosen," a rending meditation on the destruction of World War II. But Kurt Masur, whose final season as music director began that night, did not choose to dwell on lamentation.

Instead, Brahms' "German Requiem" offered the first possibility of joy - not of simple-minded escapism, or indefinitely postponed redemption, but of someday shaking off the grim numbness of these past days. In this time, I have, without intending to, deprived myself of music, and I do not think I am alone. Radios are tuned to talk and news, some stores and public spaces have muted their PA's, and the constant, global clang of tunes that fill the air in New York City has been attenuated.

So the Philharmonic's return to the stage after a period of quiet echoed an earlier day, when concerts were rare and more momentous, and music was a live art. Brahms' Requiem can be a distant, brooding work, but this performance was detailed and fluid and full of motion, as if sculpted out of still-warm wax. Soprano Heidi Grant Murphy was exquisitely seraphic. Baritone Thomas Hampson supplied thoughtful thunder. And the orchestra discovered a trembling and fire I had not heard in this piece before. As a chorister told me on the subway afterwards: "The meaning of this piece has changed. It's not just about abstract death."