Sentence:  His rage assumes a religious form ; that is , on the basis of his own sinfulness and abject wretchedness , Piepsam becomes a <WSD>prophet</WSD> who in his ecstasy and in the name of God imprecates doom on Life - not only the cyclist now , but the audience , the world , as well : `` all you light-headed breed '' . 
Meaning of the word marked with <WSD> tags:  an authoritative person who divines the future