John Bunyan’s The Pilgrim’s Progress was a book that fired Vaughan Wil-liams’s imagination for half a century. His fascination with it began in 1906 when he composed the incidental music for a dramatisation performed at Reigate Priory in December 1906 (repeated in London in March 1907). He returned to it in 1922 for the short ‘pastoral episode’, The Shepherds of the Delectable Mountains, then for Edward Sackville-West’s 1943 radio play, as an inspiration for the Fifth Symphony, and finally for his great operatic ‘morality’, The Pilgrim’s Progress, first staged at Covent Garden in 1951 – a work that has increasingly come to be seen as one of Vaughan Williams’s crowning achievements.

Boult was involved in preparations for the first performance of The Shepherds of the Delectable Mountains and conducted it on a number of occasions in the 1920s; he also conducted the incidental music for Sackville-West’s radio version and, of course, gave many performances of the Fifth Symphony. He made a BBC recording of The Pilgrim’s Progress in 1959 and, following a concert performance at the Royal Festival Hall, he recorded it for EMI in 1971.

Vaughan Williams’s agnostic perspective on Pilgrim’s Progress led him to make some changes to Bunyan for the operatic ‘morality’, altering the central character’s name from ‘Christian’ to ‘Pilgrim’. He gave his reason for this in a letter to Rutland Boughton, just after the work’s premiere in May 1951: ‘I, on purpose, did not call the Pilgrim “Christian” because I want the work to be universal and apply to anybody who aims at the spiritual life whether he is Xtian Jew, Buddhist, Shintoist or 5th [!] day Adventist.’

Boughton had suggested a performance of Pilgrim’s Progress at the Three Choirs Festival, to be given by the Covent Garden company in Worcester Cathedral. In the same letter Vaughan Williams explained why he would resist this: ‘As regards the Cathedral – it is, to my mind essentially a stage piece & I said I wd not allow it in a hall or church till it was fully established on the stage.’

Bunyan’s Pilgrim’s Progress also had lifelong significance for Boult.