In writing about Andrei Bely’s theory of Symbolism, it is common for academics to note that he believed art (which includes his own imaginative literature) to be capable of initiating a real spiritual transformation within an individual. Whilst this idea is considered to be central to Bely’s theory of Symbolism, very few academics go beyond recognising it as his ambition. This study comprises a discussion of Bely’s treatment of ideas, his influences and, using his theoretical writings in conjunction with a relevant scheme taken from Anthroposophy (of which Bely was a devotee), a process through which Bely hoped to achieve his ambition of initiating spiritual transformation. This scheme breaks down the ideas which contribute to Bely’s process of spiritual transformation into three successive stages, entitled: Imagination, Inspiration and Intuition, which are then used to enact a reading of Bely’s novel Petersburg, with a focus on the character arc of the novel’s protagonist, Nikolai. Drawing on Bely’s belief that his imaginative literature may be insufficient in passing over the esoteric knowledge required to initiate such a transformation, it is argued that his theoretical essays act as a buttress, which clarify the supposed teachings of his imaginative literature using a shared system of literary symbols which are reflected in both his theory and his fiction. Such an intimate relationship between a writer’s imaginative literature and their theoretical writings, in which they rely on one another to achieve an ultimate goal, is unusual. But considering them in this way: in which Bely’s theoretical essays act as a description of a process, and his novel Petersburg as an illustration of the process, produces a new and original reading of the novel Petersburg, and qualifies as an elaboration on the topic of spiritual transformation within Andrei Bely’s aesthetics.