Sonnet 43 follows the template for a Petrarchan sonnet, a genre of lyrical poetry defined more than four centuries before Browning by Italian poet Francesco Petrarca (1304-1374) in the earliest decades of the Renaissance. Sonnet 43, however, both is and is not a Petrarchan sonnet. Although structurally the poet follows the conventional formal expectations—14 lines of iambic pentameter following the rhyme scheme ABBA ABBA CDECDE—thematically the poem breaks radically from its own defined literary context.

Petrarch believed that the sonnet, Italian for “little song,” was the perfect vehicle for exploring love and the dynamics of affection and yearning. Across more than 20 years, Petrarch would pen more than 350 sonnets, each a love poem for a woman known to contemporary readers only as Laura. Given that Petrarch studied for the priesthood, his love sonnets are infused with the aura and elevation of Christian vision. So far, this sounds similar to Browning. However, Petrarch never had so much as a conversation with the woman he worshipped. Thus, the classic Petrarchan sonnet centers on unrequited love, a fusion of ideal love and deep sorrow. That Browning would take that literary model and use it to create sonnets that celebrate a fulfilling and immediate passion gives the Petrarchan sonnets of hers a radical buoyancy and sensuous energy.