It was the concert many suspected we would never hear. Yet, on Sunday, nearly two years after he stepped back from performance following the diagnosis of his “serious neurological condition”, Daniel Barenboim was back. Back in the London to which he has given so much, back at the Proms which loves him, and – every bit as powerful in its defiance of calamity – back with his West-Eastern Divan Orchestra of musicians from Israel, Palestine and other Arab and Muslim countries.

In such circumstances, Barenboim’s determination to return felt heroic. The Royal Albert Hall was packed to acclaim him. But the strength of will, always a feature, comes at a visible cost now. Barenboim is far frailer, moves slowly on and off the platform, ascends the podium carefully, sits to conduct, and directs with only minimal gestures.

The music-making is different, too. The physicality of the past is not there. The impetuousness has gone. Well, almost gone. Barenboim can still conjure an instant response from his players with a tiny flick of the baton when he chooses. But the grip remains. There was an austere depth, even a solemnity, to his performances of Brahms and Schubert. It echoed the Olympian late concerts of Otto Klemperer, with whom Barenboim the tyro pianist performed in the 1960s.

In Brahms’s violin concerto, Barenboim and Anne-Sophie Mutter simply ignored the press-on modern performance fashion altogether. Instead, theirs was an unapologetically sombre and reflective reading, with collaborative seriousness front and centre. Mutter’s tone ranged from full-blooded to gossamer fragile. The orchestra’s oboe principal – the West-Eastern players are not named in the programme for grimly obvious reasons – played his andante solo exquisitely. As an encore, Mutter played the sarabande from Bach’s second partita “as a musical prayer for lasting peace in the Middle East”.

Barenboim’s handling of Schubert’s “Great” C major symphony after the interval was equally uncompromising. Instead of rushing it, as too many do, he allowed the symphony’s “heavenly length” – in Robert Schumann’s phrase – to unfold at its own pace. The conducting grew more animated and the playing had the requisite grandeur. The result was Schubert’s extraordinary symphony as it ought to be heard but rarely is. It was already an unforgettable evening. This performance alone made it a great one.

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