We talk a lot in this guide about how strange the love Clare describes in “First Love” is. This is true—the love described in this poem is unusual both in the sense that it goes against the rules of normal life, and in that Clare's account of it defies the conventions of most love poetry in the period. However, the experience Clare describes isn’t unprecedented, and there are clear parallels to others’ accounts of especially overwhelming experiences of love.
One especially interesting parallel is between this poem and Sappho’s “Fragment 31.” In it, the famous ancient Greek poet describes herself experiencing a love that “puts the heart in my chest on wings.” When she looks at her beloved “no speaking / is left in me / no: tongue breaks and thin / fire is racing under skin / and in eyes no sight and drumming / fills ears / and cold sweat holds me and shaking / grips me all, greener than grass / I am and dead—or almost / I seem to me.” It’s worth quoting her poem at length because the similarities between it and “First Love” are so pronounced. She too experiences love as a loss of ordinary bodily function and sensory capacity. She feels fire burning beneath her skin, just as Clare’s speaker feels the blood burning around his heart.
Perhaps most interesting for us, as careful readers of poetry, is the similarity between Clare’s simile, “my face turned pale as deadly pale” and Sappho’s “greener than grass I am.” Sappho’s simile is less obviously “broken” than Clare’s—she does compare something to something else, namely, herself to grass. Yet it’s hardly clear what she means. She’s not physically turning green, and green didn’t have the same connotations of jealousy as it does now. Furthermore, she’s not simply as “green” as grass, but “greener” than it—the comparison between herself and the grass is insufficient to account for her own experience, just as Clare can find nothing to compare the lover’s pale skin to but the skin itself.
This is not to say that Clare was directly influenced by "Fragment 31," although it’s certainly possible—the poem was a favorite of the Romantic poets, and both Shelley and Keats were inspired by it. But it is helpful to read “First Love” not just as an expression of unusual personal experience, but as part of literary tradition. Some other interesting comparisons could be made to the ecstatic experiences of Christian mystics, like Teresa of Avila, whose writings recount visions involving feelings of overwhelming passion towards Jesus. Clare is using the freedoms afforded by poetry to find the imagery and language to express the inexpressible.