Chapter 3 traces the movements of Shelley’s ideas and attitudes toward religion throughout his life and writings. It views Shelley as a far more nuanced religious thinker than is often implied by critics. It identifies the ambivalence with which Shelley, a self-styled atheist, approaches religious belief—especially Christian modes of belief—and the ways in which Shelley wrestles with and subverts the boundaries between the secular and the religious. The chapter examines how Shelley’s imagination adapts the language of religious belief in order to articulate poetic vision and experience. It traces many of Shelley’s allusions to the Bible and identifies the ways in which Shelley ‘incessantly reorchestrate[s]’ Biblical language in his works. It identifies the treatment of religion in other Romantic poets, such as Wordsworth and Blake, and shows how Shelley’s poetry departs from their approaches to religion. The chapter also probes a recurring idea in Shelley’s poetry and writings that there is some power or spirit that affects human souls, that originates within or, just possibly, beyond humanity, and has characteristics that influence and are influenced by poets. For Shelley, poetry is religion and poets are prophets and seekers of truth. The chapter also discusses Shelley’s religious prose and the ways in which his writings about God, belief, and religion ‘[reveal] a double rhythm’ in which Shelley ranges from scientific examination to ‘eruptions of latent feeling’. The chapter concludes with a study of Shelley’s final poem, the unfinished Triumph of Life, showing that throughout the poem there ghosts a ‘Christian belief-system that is never wholly abandoned or forgotten’.