Wordsworth as "Poet of Nature" (symbol)
As noted previously, Nature was a key concept for the Romantic poets, and it carried assumptions about systems of religious belief. In this apostrophic address, Shelley is expressing his view that Wordsworth is a poet of the deist worldview that God and Nature and inseparable. Part of the power of Wordsworth's early poetry, for Shelley, came from how it expressed the power of nature as a force to develop morality and human sensibility.
"Fled like sweet dreams" (simile)
This simile—a rhetorical figure that compares one thing with another through the terms "like" or "as"— draws on Wordsworth's own language from his famous "Intimations" ode, a poem that exerted a great influence over Shelley. Just as "sweet dreams" disappear quickly after waking, Wordsworth's poetry, particularly the Intimations Ode, express how "Childhood and youth, friendship and love's first glow" also pass quickly away, but that a deeper appreciation of nature and of life can emerge in later life despite these losses.
Wordsworth as "a lone star" (simile)
This is the first of two elaborate similes that Shelley uses to express what Wordsworth meant to him. In the simile, Wordsworth is "a lone star" and the light from the star is Wordsworth's poetry, which guides Shelley, turned here into a "frail bark"—a small ship sailing alone through the difficulties of life (expressed in the simile as "winter's midnight roar"). That is, Wordsworth's poetry was a guiding light to Shelley through hard times in his life, when all else seemed dark and hopeless.
Wordsworth as a "rock-built refuge" (simile)
This is the second of the two similes that Shelley uses to express what Wordsworth meant to him. Here, Wordsworth is the "rock-built refuge," both sturdy and unshakable, and removed from the tumult of "the blind and battling multitude" that are experienced in everyday life. Wordsworth is not only a guiding light, then, but also a place of refuge and escape from the chaos of life. Whereas the multitude are blind, Wordsworth represents the eternal truths of nature, which have the lastingness of something built of stone.
"Thy voice did weave / Songs" (metaphor)
Shelley uses a common metaphor here of the poet as singer, but compounds it with the metaphor of weaving. This expresses on the one hand Wordsworth's position in the canon of great poets, often considered "singers," but on the other hand the artfulness of his poetry, which is like a woven tapestry in its complexity and beauty. But the most important part here, for Shelley, is that Wordsworth's art was devoted to "truth and liberty."
Death (metaphor)
Shelley uses the metaphor of death to describe the dramatic change in Wordsworth' political leanings. The poem reads like an elegy, though of course Wordsworth is still alive. His political betrayal of the principles represented by the French Revolution—political liberty and equality—is tantamount for Shelley to him ceasing to exist. Shelley had never met Wordsworth, so Wordsworth to him existed only through his books. With the publication of The Excursion, the Wordsworth that Shelley had previously known, the poet that he thought Wordsworth was, had ceased to be.
