Eat the fire, serpent, glass, when you are hunger-heady. Nothing happens to your heart till your heart is ready.
Ecstasy is but a name, in it lies a presence like a little candle lit or a small obeisance.
Eat the serpent, fire, glass when your heart is heady. Harm or blessing come to pass if the heart is ready!
Think of the poem as a piece of advice wrapped in a strange, almost dangerous image. The speaker tells you to eat fire, serpents, and glass, which sounds like a circus act or a trial of endurance, but the real point lies in the condition attached: only "when you are hunger-heady," only when your heart is ready. Nothing happens, the poem says, until that moment arrives.
The middle stanza shifts to a quieter register. Ecstasy, the speaker suggests, is just a name, and what actually lives inside it is modest, like "a little candle lit" or "a small obeisance," a slight bow. So the great, blazing experiences the poem opens with turn out to be rooted in something small and humble.
The final stanza repeats the opening with the order of the dangers shuffled and the stakes made clear: harm or blessing may follow, and the readiness of the heart decides which. The mood is hypnotic and chant-like, its rhymes and repetition mimicking a spinning dance, with a warning tucked inside the rhythm.