Christopher Marlowe's short lyric "The Passionate Shepherd to His Love" has exercised an influence on English verse which hardly seems indicated by the limpid faux-naif quality of the poem itself, written in simple four-line stanzas, each composed of a pair of simple rhymed octosyllablic couplets. R.S. Forsythe traces a whole host of imitations in English and in Continental verse of Marlowe's pastoral song, and concludes that "The Passionate Shepherd to His Love" has exercised, for over three hundred and thirty years, upon English poetry an influence, direct or indirect, which is equalled by that of few poems; second, that, probably because of the popularity of these verses, a literary device was created -- the invitation to love -- which, in one form or another, adapted in this way or that, has persisted down into our own days. (742)

But I would propose that an examination of the metaphor and simile in this poem reveal a greater complexity than we might initially assume, and I will conclude by examining an earlier critical reading of Marlowe's poem by Louis Leiter, which suggests a much grander metaphorical meaning for the poem overall.

We must begin with the question of the poem's genre. Marlowe's "Passionate Shepherd" presents us with pretty much the textbook definition of pastoral -- a genre that Dr. Samuel Johnson in a later era would famously refer to as "easy, vulgar and therefore disgusting" (105). Johnson meant "easy" to refer to the life of ease presented in the pastoral vision, and "vulgar" to refer to its emphasis on simple rustic pleasures enjoyed by unsophisticated people. In essence, the pastoral genre places a sort of metaphoric costume on the poet: he speaks in sophisticated and finely-wrought verse a song which is presented...

It was an established genre in Ancient Greece -- the Sicilian Greek poet Theocritus provided a classical model for Marlowe's work here. Theocritus was consciously imitating the actual improvised songs or traditional songs of illiterate shepherds: as late as the 1950s the naturalist Gavin Maxwell was able to record actual shepherd-boys in Sicily having singing contests during the long lonely tedium of pasturing their flocks. In other words, the poet is metaphorically posing as a shepherd, and the poem itself is troped as his "song." In this case, as noted by Forsythe above, the genre of song is one that Marlowe himself invented: it is an erotic invitation.
The use of metaphor and simile within the poem's text is fairly limited, though. "Prove" is to some extent a metaphorical term to be used with pleasure, because it carries scientific and mathematical connotations. Cheney notes that "Marlowe's dominant naturalist imagery (valleys, groves, hills, fields, woods, mountain),together with his scientific-sounding discourse -- 'prove' (experience), 'yields' -- moves his view of pleasure into the philosophical domain." (539). He is right that the central metaphor in the first stanza is paradoxical, presenting simple pleasure as complex intellectual activity. In the second stanza, the natural phenomenon of birdsong is presented metaphorically as an intricately organized form of art -- like Marlowe's poem itself -- designed to entice the beloved. In lines 7 and 8 of the poem, Marlowe introduces a more complicated metaphor which also includes a pun. When the shepherd tells his mistress that they can watch other shepherds pasturing their sheep "by shallow rivers, to whose falls / melodious birds sing madrigals," the metaphor is obvious that…