Every now and then, you are privileged — truly privileged — to attend some performance. And that was the case on Thursday night, when Alisa Weilerstein played the Elgar Cello Concerto with the New York Philharmonic, guest-conducted by its former music director, Zubin Mehta. Ms. Weilerstein is 24 years old, the daughter of two celebrated music teachers. There are two important 24-year-old cellists in the world: Ms. Weilerstein and the Koreanborn Han-Na Chang.

And how old was Jacqueline du Pré when she made her famous recording of the Elgar Concerto? But 20. Of course, Sir John Barbirolli, conducting the London Symphony Orchestra, had something to do with the greatness of that recording, too.

Elgar begins his concerto with the cello alone, and Ms. Weilerstein tucked into the music with abandon — yet a controlled abandon, if you will allow that. She made a beautiful sound, and that sound proved variable: It was lighter or darker, richer or tarter, depending on the needs of the music. Ms. Weilerstein sang and sighed on her cello, using a judicious amount of portamento. She also used a judicious amount of rubato.

Musical instincts such as these cannot be taught; they are part of her makeup, lucky girl (and lucky audiences).

You did not need to give any thought to technique, as Ms. Weilerstein’s fingers were absolutely sure. This allowed us, and her, to concentrate solely on the music. She gelled with the conductor, Mr. Mehta, looking at him almost constantly — certainly more than any orchestra player did!

The second movement featured the right shuddering and shimmering, and the third movement — Adagio — was a wonderful song: breathed with utter naturalness. The final movement was marked by what I must call an elegant savagery, or a savage elegance, if you like — exactly what is necessary. Ms. Weilerstein managed to impart a feeling of improvisation, as though the notes were just occurring to her to play.

Throughout the concerto, she played with extreme freshness and musical love. May she never lose this approach — this mindset — as the years roll by.

I must tell something on myself: When Ms. Weilerstein was finished, the audience clapped heartily, but stayed seated. So did I — and I felt like a heel for not standing. This was a performance that one should have acknowledged on one’s feet.

Then Ms. Weilerstein did something I regarded as a bit of a mistake: She played an encore, the Bourrée from Bach’s C-major Cello Suite. She played it decently, although not nearly as well as she had played the Elgar. It was a little unclean, and just slightly wayward. Also, it was too long for the occasion. But mainly, the encore was not necessary — was not an enhancer. To me, it distracted from the stunning performance we had just heard.

Ms. Weilerstein should not have said another word.

Mr. Mehta, who had conducted with notable taste during the Elgar, came back for Bruckner’s Symphony No. 7, one of that composer’s great symphonies, and, indeed, one of the greatest symphonies in all the literature. Its slow movement, Adagio, has a special immortality.

The ex-music director drew an extraordinary sound from the orchestra: warm, generous, hopeful, beautiful. You are not supposed to hear that in Avery Fisher Hall, or from the New York Phil. Under Mr. Mehta, the Seventh was big-boned and muscular, but also wistful and tender. One could sort of forget the conducting and ponder Bruckner: his sonorities, his architecture, his everything.

Of course, there were problems here and there, little glitches. The second movement began with a botched entrance, and the horns struggled in the last movement. (What else is new?) But these were nothing, compared with the excellence of the performance overall.

The Scherzo was less intense, less propulsive, than usual; instead it expressed a striking gemütlichkeit — and not just in the Trio, which was wonderfully warm and swirling. The Finale began exactly as it should: with quivering anticipation. And it concluded with huge nobility, Bruckner washing you in his E-major bath.

Mr. Mehta ended the music almost matter-of-factly — he simply stopped when the score does. He attempted to put no personal stamp on it. He left the stamp to Bruckner, which was marvelous.

As individual players were called on to take bows, the other players clapped enthusiastically. This is something you seldom see. The orchestra seemed to know that it had been a first-rate night. As I said in a review last week, Mr. Mehta’s tenure in New York — 1978 to 1991 — was controversial. But there was nothing controversial about his recent concerts as a guest: The two I attended were superb.

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Bach’s St. Matthew Passion was heard at Carnegie Hall on Saturday night — and it wasn’t even Easter. Hallelujah. If ever there was a piece for all seasons, it’s “the Matthew.” The conductor was Helmuth Rilling, and the chorus was the Carnegie Hall Festival Chorus. These are people who come from far and wide to participate in Carnegie’s weeklong Choral Workshop. This program was begun by the late Robert Shaw, back in 1990.

Mr. Rilling is one of the most famous Bach men in the world, and is a pillar of his native Stuttgart. I should note that Mr. Rilling is more than a Bach man: Try his recording of the Mozart Requiem (with Arleen Auger as the soprano). His conducting of the Matthew on Saturday night was moderate, and I mean that as praise, not disparagement. He was sensible, reasonable, and convincing all the way through. Tempos were neither slow nor fast — they were simply right-feeling. Mr. Rilling was not at all interested in “period” correctness, but rather was interested in the music, and its meaning.

Also, he conducted this threehour work from memory, which might be put down as a stunt, but which was, in this case, natural, even inevitable. Mr. Rilling has this music in his bones.

The Carnegie Hall Festival Chorus proved well drilled, alert, and excellent. Its cries, when portraying the mobs of the Passion, were properly terrible.

Mr. Rilling had with him a laudable string of vocal soloists, almost all possessing exceptionally beautiful voices. Leading the pack was James Taylor, the tenor from Houston who took the part of the Evangelist. Mr. Taylor has one of the freshest, loveliest, and sweetest voices in the business. In fact, I am tempted to call him Sweet Baby James, but he has no doubt heard such comments all his life.

He sang with almost unseemly ease, handling Bach’s punishing high notes as though they were normal. And he did not neglect interpretive expressiveness: The Evangelist must not be musically or dramatically neutral. To be sure, Mr. Taylor faulted every so often, hitting a clinker. His first note and first recitative happened to be hideously flat. But he was never so off pitch again, and if you can find a better Evangelist, the man ought to be rich.

The German bass Klaus Häger sang the part of Jesus, and did so with competence and conviction. Words from him had deep meaning, but no melodrama. A Dallas mezzo with the nifty name of Gigi Mitchell-Velasco was a lastminute replacement, and she did a fabulous job. She owns a beautiful, arresting, and moving voice, and if she seemed a tad underpowered at times, that mattered little.

The evening’s soprano was Sibylla Rubens, a German, heard on several recordings, including the new Mozart Requiem conducted by Christian Thielemann. In the Matthew, her singing was amazingly touching and sincere, and it included what I can only call a kindness. Her rendition of “Aus Liebe” was heartbreaking.

And I can’t help asking: If you sing like Ms. Rubens, are you Rubenesque?

A Stuttgart baritone named Michael Nagy was highly effective — streamlined, tasteful, and pure. He had the honor of singing the aria “Mache dich, mein Herze, rein,” one of the most sublime things ever written. And the American tenor Thomas Cooley acquitted himself well, even if he occasionally strained and pinched.

The orchestra was the Orchestra of St. Luke’s, playing ably, attentively. They were “fully committed,” as the restaurant people say, in another context. Once in a while, their playing took on that plodding, head-nodding quality, fatal to Bach. But that was only once in a while. The orchestra was integral to the entire performance, and the oboist was outstanding.

In all, Bach’s St. Matthew Passion had its full impact — and that is quite an impact, you may agree.