Here is the Keats who gave up contact with Fanny Brawne because it was too painful, who in the end asked that his Shakespeare and other books of poetry be removed, who instructed grimly that his epitaph should be "Here lies one whose name was writ in water". Here is the Keats who was a trained surgeon, who had nursed his brother through the consumption that had killed him, who recognised the coming agony, tried to prevent it by suicide, and was lovingly, and religiously, frustrated by Joseph Severn. Here is the Keats who was horribly afraid of the dark, and considerately brave. He was a tough intelligence, and Burgess uses one of his most uncompromising statements as his own epigraph. "I would reject a petrarchal coronation – on account of my dying day, and because women have Cancers." The grim voice of the dying surgeon speaks in counterpoint to the classical, flowery poet.

Burgess's novel – like all his novels – is about body and soul. Belli's blasphemous sonnets about the Incarnation represent one embodiment of spirit in earthy language. Burgess's Keats's dialogue, with its deliberately tasteless and inconveniently frank wit, is another embodiment. The soul is perhaps only the breath, the word of mouth. The title of the novel, Abba Abba, represents the cry of the dying Christ on the cross to his unhearing Father. It also represents, as Belli tells Cardinal Fabiani, the octave of the rhyme scheme of a petrarchan sonnet. For Burgess's Belli this sonnet is a kind of Incarnation. He says:

"The sonnet form must have existed in potentia from the beginning, but it was made flesh such as Petrarch. Behind the thousands of sonnets in the world, in Tuscan, Roman, French, German, even English, shines the one ultimate perfect sonnet… The wordless sonnet that still rhymes, that says nothing, having no words, but yet speaks… the ultimate statement whose meaning is itself. What is this, your eminence, but the true image of God?"