The Old Testament Book of Job is the only book in the Bible to seriously tackle the problem of pain and evil: How is it that, when God is good and God is omnipotent, there is so much pain and evil in the world? In the King James version the book is poetically inspired, but theologically baffling. It inspired English poet, mystic, painter and engraver William Blake to one of his finest works, a series of 22 engravings illustrating the Book of Job, made towards the end of his life. Blake's engravings in turn inspired Vaughan Williams to one of his finest scores, a ballet in nine scenes whose sets and choreography are closely modelled on Blake's engravings.

Each of them adapted the story somewhat to reflect their own beliefs. Blake concentrates on Job's self-righteousness as the cause of his troubles. He implies parallels with the English nation in his time, the dawn of the industrial revolution - in a state of spiritual sickness and under the domination of a materialist philosophy, whose people are oblivious to the spiritual nature of man. Vaughan Williams was also aware of the spiritual side of man, but expressed it in music instead of the word and the graphic arts. He was not an orthodox believer any more than Blake, but like Blake he was deeply aware of and concerned with man's spiritual side.

The idea for Job came in 1928 from Geoffrey Keynes, a famous surgeon, ballet lover, and the first great Blake scholar. The 22 engravings were adapted into nine scenes by Keynes and his sister-in-law the artist Gwendolen Raverat, who was Vaughan-Williams' cousin. The music was completed in 1930 and was first performed in a concert (non-staged) version at the Norwich Festival that year. The ballet was premiered in London in 1931 by a group called the Camargo Society, predecessor of the Sadlers Wells Ballet, now the Royal Ballet company. On this occasion a reduced orchestration was used to cope with the restricted space in the theatre pit.

Musically Job is the centrepiece of Vaughan-Williams' output. It draws together threads from his earlier works such as Lark Ascending and the Tallis Fantasia, and points the way to later and violent works such as the 4th and 6th symphonies. As in the Tallis Fantasia, there is much use of clashing major and minor thirds and a rising perfect fourth. But in Job this contrasts with the augmented fourth, the diabolus in musica of mediaeval composers, and here representing Satan himself. More than in any other of his works, Vaughan-Williams here moulds all these elements into a complex yet coherent musical structure which manages to follow the sequence of Blake's engravings with remarkable accuracy. For listeners accustomed to the 4-movement shape of a symphony, this can make Job seem a difficult work to follow at first hearing. The subtitle "A Masque for Dancing" conveys two important points. Firstly it is not a normal ballet, using mime in a series of relatively static tableaux, interspersed with dances both stately (e.g. Job's sons) and violent (Satan's dance). And secondly it emphasises the link with Blake and tradition by the use of old dance forms, such as Sarabande, Minuet, Galliard and Pavane.

Scene 1: In the gentle Introduction we meet Job and his family - his wife, his sons and his daughters. They sit under a tree on which hang musical instruments, mute and unused. In the alternating major / minor third tonality (this first gentle theme represents Job himself) we realise that all is not as peaceful as it should be. At the first loud entry Job blesses his children to an important descending scale. Briefly we hear Satan's short, jagged motive, and then in rising fourths Heaven opens to reveal God in majesty. But here too there are tensions in the curious wind chords which answer the rising strings. The Sarabande of the Sons of God is a rich dance; God admiringly points out Job to Satan, but Satan offers a challenge - destroy Job's prosperity and even Job will curse you! God accepts the challenge and, in a loud descending theme similar to Job's own blessing to his children, dares Satan to do his worst. The stately dance ends on a threatening unison note.

Scene 2: Satan's Dance of Triumph. A fast and wild dance, based on a whole tone scale and Satan's motive we heard in Scene 1. The tonality is unstable and the accompanying rhythms are relentless and disrupted. Near the end the brass blaze out a sarcastic Gloria in Excelsis Deo.

Scene 3: In an archaic minuet we see Job's sons and their wives dancing. The style is gentle and simple, but the tonality and harmony is unexpectedly wrong. This is not honest grace but vanity, full of voluptuous pride. Satan enters, and Job's blessing theme is blasted out, now become a harsh curse. The dancers are struck dead and the music ends bleakly.

Scene 4: Job's Dream. Unaware of the disaster to his sons, Job stirs in his calm sleep. The music swells and to the blessing/curse motive Satan appears and conjures up a terrifying sequence of visions - plague, pestilence, famine, battle, death. The music is jazzy but frequent augmented fourths make it harsh and aggressive.

Scene 5: Dance of the three Messengers. A solo oboe introduces lamenting woodwind, who tell Job of the death of his sons and their wives, and the loss of all his wealth. It turns into a funeral cortege, but Job still blesses God. (He cannot conceive that the evils are in any way due to his own faults.)

Scene 6: Dance of Job's Comforters. Satan's theme introduce Job's "comforters". Their dance is at first one of pretended sympathy, but develops into anger and reproach as they blame Job for his own disasters. An oily saxophone solo highlights their hypocrisy. To another version of the blessing/curse theme Job finally cracks and curses God. At this heaven gradually opens (as in scene 1) and reveals, to the entry of the full organ, Satan seated in triumph on God's throne. Job cowers in terror as the vision fades.

Scene 7: Elihu's Dance of Youth and Beauty. At last real comfort comes to Job in a violin solo reminiscent of the Lark Ascending. It is clear from the clean simplicity of the melody that Elihu comes from God, and in the solemn hymn-like Pavane of the Sons of Morning it seems that Heaven is offering Job a fresh start.

Scene 8: In his now familiar jagged theme Satan comes to God to claim his victory. But in the most powerful version of the blessing/curse theme God pronounces his curse on Satan and banishes him. To an energetic and rustic sounding dance in triple time the Sons of Morning drive Satan out from Heaven. When this stops abruptly we see Job and his friends preparing an Altar under the tree, as in scene 1. But now the instruments are not mute but being played. Gradually the Altar Dance incorporates the Pavane of the Sons of Morning from scene 7 and moving richly through different keys climaxes on three extraordinary bi-tonal chords and then, like scene 1, ends on a powerful unison note.

Scene 9: Epilogue. Job is an old man and his wealth is restored, but he is humbled. In music we have not heard since scene 1 we see him giving gifts and receiving gifts from love alone, and no longer self-righteous in his cold distribution of charity. Because for Blake self-righteousness is the only unforgivable sin, and "the letter [of the law] killeth, but the spirit giveth life".