The British composer Sir John Tavener is famously devoted to the Orthodox Church that has inspired nearly all of his music. Or he was, until a recent rift with his spiritual advisor soured him on Orthodoxy. Now, he calls the strict musical code by which he used to live a “tyranny,” and his latest work is based on Islamic texts. “A forthcoming work he is planning to write, as if to emphasise his new-found freedom from Orthodox principles, is a theatrical composition based on the life of Krishna and influenced by Mozart’s Magic Flute.”