I sat through an 8-hour choral epic on a beanbag. Was it worth it?

Above us, seated in the circle and upper circle of the city’s grand Usher Hall, concert-goers had dressed up for the occasion. One stately dame sympathised with another, headed down to slump on a beanbag in the stalls. “I’ve been practising getting up,” she reassured her.

Soon afterwards, at 2.30pm, the lights dimmed and, to the sound of a lone soprano and the wail of a duduk (a sort of short eastern oboe), Tavener’s lengthy sonic train left the station; destination unknown.

His work, which premiered in 2003 in London with Tavener in attendance, is a fusion of doctrine and arcane religious rites, spanning Hinduism, Judaism and Christian liturgy, with a heavy dose of the iconography of the Orthodox faith, to which the late English composer converted in 1977. It takes its title from a report in the Synoptic Gospels that “the veil of the temple was torn in two from top to bottom” when Jesus died, symbolising the dawn of a new direct relationship between God and mankind.

If Tavener’s piece demands prolonged concentration from its audience, it asks much more of its performers and conductor, in this case Swedish-born Sofi Jeannin. She was on stage for most of the eight hours, stoking the engine and even joining in song at the climax.

The directorial feat was almost as impressive. Thomas Guthrie choreographed the massed ranks of the Edinburgh Festival Chorus, the Monteverdi Choir and the National Youth Choir of Scotland, who all moved seamlessly around the darkened auditorium while the music progressed through eight cycles, with synchronised mood-altering lighting shifts.

Before the music started, and once the technical crew had audibly put in orders for espressos and flat whites, Nicola Benedetti, the virtuoso violinist and director of the festival, prepared the audience. “I don’t expect you all to stay still, and the doors will unlock after the first two cycles,” she said cheerily. She had known Tavener personally, she added, and staging his masterpiece – a “meditation on the unifying essence” of life – was a “unique and singular moment”.

Written in five languages including Aramaic and Sanskrit, the music swells and diminishes, weaving its profound themes. Sometimes the sound is mighty: bells, cymbals, organ, drums. Sometimes solo voices chant simple liturgy, in the varied guises of priest, cantor or monk. A string of these faultless, extended performances such as from bass-baritone Florian Störtz, who sang Christ, were among the most compelling sequences.

A Tibetan horn marked major moments of musical transition. There were even hints of a Welsh male voice choir, while in other passages we heard the limited range of a low church harmonium. It might all have amounted to pastiche, if Tavener’s intent was not so convincingly serious.

Each succeeding cycle was signposted by the ceremonial lighting of a candle to ward off “chaos”, creating a ritualistic, inclusive atmosphere, as audience members intermittently sidled off to the loo or for a consolatory sandwich in a breakout zone. Segments with familiar western choral settings were repeatedly disrupted by the blending of traditions, with an undercurrent of subversive dissonance running through the entire score.

By the fifth cycle, with half the chorus lining the back of the hall for the Lord’s Prayer and a soprano singing from the circle, everyone had adapted to a new way of life. “Blessed be the one who sits on a beanbag with all devotion,” we thought, customising a line of text.

It is annoying when a concert-goer boasts about some feat of cultural endurance, implying you really had to be there. But this event delivered. During a break, I overheard one older man phone home for permission to stay on. “I really want to be here for the end,” he explained, “because it seems it is building into something wonderful.” When the final words, shanti shanti shanti, drawn from the Upanishad hymns and echoing the close of TS Eliot’s The Waste Land,  did ring out, it was wonderful indeed.

Photograph by Andrew Perry