But words came halting forth, wanting invention's stay; / Invention, nature's child, fled step-dame study's blows; / Thus great with child to speak, and helpless in my throes. / Biting my truant pen, beating myself for spite, / 'Fool,' said my muse to me; look in thy heart, and write.
-- Speaker (Astrophel) (Sonnet 1 paragraph Lines 9-14)

Importance: This quote serves as the closing couplet to the first sonnet of the sequence and introduces the reader to the speaker's anxiety about his ability to craft poetry at the same time that he is possessed by love for the Beloved. His muse's response, in which she refers to him as "fool," indicates that the creative process is much more simple than the speaker assumes, and Sidney therefore opens the sequence under the assumption that his speaker will be speaking from the heart.

Or would she her miraculous power show, / That, whereas black seems beauty's contrary, / She even in black doth make...
-- Speaker (Astrophel) (Sonnet 7 paragraph Lines 9-11)