The Israel Philharmonic is never shy of a gala but this one was different; the finale of a festival bidding a final farewell to the leadership of Zubin Mehta, the IPO’s chief conductor of half a century (beginning as Music Adviser in 1969, graduating to Music Director in 1977).

That there was rare emotion crackling around the Bronfman Hall in Tel Aviv was evidenced as soon as Mehta appeared from the wings. Making his way carefully to the podium, aided by a walking stick, he looked his 83 years — but rather better than had been feared only a year ago after a prolonged period of serious illness. His audience — his audience — stood and applauded and cheered, before a note had been heard, before he even reached his accustomed place of so many decades.

Mehta, ever humble, turned to his players and gave the downbeat for the national anthem, Hatikvah. The audience, already standing, sung along in tones reverenced rather than dutiful.

As if coming to understand that this anthem, on this day and from every person in this hall, was his anthem, Mehta turned, arms still waving, and made eye contact with us (with each of us individually, it felt) and we followed his beat. Not a few shed a tear. With an approving nod, Mehta turned back.

It was a moving opening to an unforgettable concert, one of the most affecting I have ever had the privilege to attend. To start with, there was ambition.

Mehta may look frail (and the widespread knowledge that he was to fly to Los Angeles for a medical procedure immediately following the concert was a sobering thought) but he didn’t make life easy for himself — and he could have, with a lighter programme. Everyone would have understood.

Instead, he had scheduled not only Mahler’s 90-minute Second Symphony (so long that it often stands alone) but also Liszt’s Piano Concerto No 2, for which he was joined by Yefim Bronfman. The pianist, a great favourite here, reminded us all that while he does not want for power, he is a magician of adroitness, his incredible technique cloaked and shaded by lightness of touch.

All of which was even more in evidence in his encore, for which, in a nice surprise, he was joined in a Dvorak duet at the piano by Mehta’s successor as Music Director, Lahav Shani.

After the interval, various IPO dignitaries appeared for a touching salute and to announce his new, honorary title, Music Director Emeritus. Mehta thanked the musicians: “Maybe they have learnt a little something from me, but that is nothing compared to what I have learnt from them, and the generations that came before.” Noting the length of the symphony to come, he kept his comments brief.

And then, the Mahler. One way to make a difficult work even more demanding is to do it the way Mehta did it. Many conductors wrest angst from jolting tempo changes and suddenly contrasting volume dynamics when it comes to this most bipolar of composers; that’s valid and often effective. Mehta’s path was more difficult, more complex and required from him the most intense concentration.

Everything flowed naturally and even, to begin with, conservatively from his baton. Then, slowly, he anatomised the work, as if every motif, every theme had its own distinctive texture, as though it came from its own individual realm. All was of a piece, and yet, strings swooped with tone so diamond-sharp as to almost draw blood. Double-basses bristled as if with static electricity. The harp danced and spun like a spider on its web. When those famous dynamic extremes came, they had been earnt and were the more powerful for it — the choir’s entry was almost on the breath and, near the end of a long concert, it was as if you could hear every heart beating.

Mehta is not best-known as a Mahlerian, yet this performance was a meeting of worlds, a progression of eras. Century met century. Viennese tradition met Webernesque modernism. And, of course, Mehta himself passed the IPO mantle on to the next.

As the orchestra’s Secretary General Avi Shoshani draped an Indian flower garland around the neck of the Parsi from Mumbai who long ago adopted the Jewish state, and as that country bellowed its thanks, everyone in that hall understood something else, too: that other artistic leaders (starting with the exciting talent that is Lahav Shani) will come, and they will build and leave their own important legacies, but that Zubin Mehta’s mark on this orchestra — like that of Leonard Bernstein before him — will be indelible.

And that is as it should be.