Pastoral verse essentially originated with the Greek poet Theocritus (ca. 275 BCE), who began the genre in part by observing and then putting to words the actions of shepherds as they guarded their flocks. Rather than adopting the realistic, but rustic, language of shepherds, Theocritus used very formal vocabulary and rhyme scheme to describe the natural setting. We have, then, the odd juxtaposition of very formal diction for very natural subject matter. In a pastoral elegy, the poet uses formal language to explore the theme of grief occasioned by the loss of a friend or person of importance, often someone dying at an unnaturally young age.
Milton's "Lycidas" exhibits several conventions of the pastoral elegy, beginning with the invocation of the muse:
Begin, then, Sisters of the sacred well,/That from beneath the seat of Jove doth spring,/Begin, and somwhat loudly sweep the string. (ll.15-17)
Milton invokes the aid of the Nine Muses,...
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