MacMillan's St John Passion, Barbican Hall

A fervent believer, James MacMillan has no time for what he's called the "instant spiritual highs" of composer-gurus like Glass, Gorecki or John Tavener.

Simplicity is part of the armour, and with plenty of splendid church anthems to his credit MacMillan certainly knows how to write an effective wide range of liturgical music for the Evangelical semi-chorus. Who were the outstanding trained voices of this "Narrator Chorus"? Guildhall students? The programme didn't tell us. Anyway, it seemed deliberate that their collective St John should take us rather briskly into the "and then...and then" of Jesus's arrest and trials, handing over to the blurrier forces of the London Symphony Chorus, who got to spit, interrogate and howl with appropriate venom. Later the chamber group wilted hauntingly with glissandoing brass to convey how sordidly the soldiers parted Christ's garments.

Though fidgety at first, the musical drama at least had the virtue of providing different languages for the various participants. Yet whether Christ's utterances would have worked much better if baritone Christopher Maltman hadn't been manfully struggling through with a throat infection seems doubtful. Despite the welcome halo of three solo violins, the Gaelic inflections and the reiterated melismas reminded me of nothing so much as Emma Thompson's portentous "I, I, I, I"s as the winged messenger in the film of Tony Kushner's Angels in America. Later, in what should have been climactic reproaches before giving up the ghost, this Jesus came across as about as appealing as Strauss's bully of a Baptist in Salome. Strauss disliked his man of God; MacMillan presumably feels the opposite about Christ, so what's going on here? After all, we know how well he can write for voices from the soulful characterisations of The Sacrifice.

At his best, MacMillan absorbs healthy influences. A short trot of Sibelian serenity, flutes against pizzicati, makes several brief but welcome appearances; brass chords let rip from the heavens of Vaughan Williams's Job to suggest Christ's other-worldliness. But by the interval we were waiting for the quick-change style to settle. In the Crucifixion sequence there were promising trombone twitches and growls straight out of The Sacrifice's ritual dances, and what developed as a Stabat Mater interlude began strikingly with burbling bass clarinet, only to go soft-focus in a larger choral haze. Would it all add up in the final, orchestra-only movement? It seemed about to with staggered eloquence from the strings, urgently shaped by Davis, and then eased too readily into film-score gestures.

This was a work I'd so much wanted to be stirred by. In the end I could muster only curiosity, passing admiration and unfulfilled expectation, which surely aren't enough for a work of this scope - a St John Passion which is never soporific-repetitive like Arvo Pärt's but not as strikingly original as Russian mystic Sofia Gubaidulina's either. Let's hope MacMillan's Violin Concerto, due to be premiered by Vadim Rapin with Gergiev conducting the LSO on 12 May, will see a return to his truly shattering best form.

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