On today’s date in 1968, London witnessed a double debut: the first concert of the London Sinfonietta, a chamber group which would go on to become one of the Britain’s most famous new music ensembles and, on their debut program, the premiere performance of a dramatic cantata by John Tavener, who would go on to become one of Britain’s most famous contemporary composers.

Tavener’s cantata was titled, “The Whale.” The London Sinfonietta’s premiere attracted the attention of both the BBC, which broadcast the work that same year, and The Beatles, who released a recording of the work on their own newly formed Apple label.

After Tavener’s religious conversion to the Greek Orthodox faith in 1977, and a near-death experience during surgery in 1990 to remove a tumor from his jaw, Tavener’s music became ever more liturgical, and, as the composer puts it, more “spontaneous.”

“The religious tradition says that only the spontaneous is true,” says Tavener. “If I find myself trying to write and it's not spontaneous, it doesn't come. And that's completely the opposite of the western concept of composition—the idea of someone slaving over something to get it right.”

In 1997, when the funeral service for Princess Diana was broadcast worldwide, it was Tavener’s serenely lyrical anthem “Song for Athene” that was chosen to accompany the Princess’s coffin as it left Westminster Abbey.