I was teaching yoga at Pentonville prison when, in 2000, John Tavener was commissioned to write a piece to be performed in the large prison chapel by the London Sinfonietta. The piece was called In One Single Moment and referred to the point at which God saved one of the thieves on the cross with Jesus. Prisoners were also encouraged to write songs with the same title and perform them at the concert. Their songs were about life turning on a single moment ? for example, when their sentences were announced, when a baby was born, waking up from a dream that they had been released. In the packed audience were prison staff and teachers, some Home Office people and prisoners. It was very impressive and moving and there was tumultuous applause and whooping at the end. I shall never forget seeing Tavener standing on the platform ? tall, thin, leaning to his right (like the Tower of Pisa), flushed and smiling. It was quite something to see large, excited prisoners slapping him on the back and high-fiving this frail-seeming man who looked as though the smallest breeze might blow him over.

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