During their own lifetime, Horace and Vergil were Rome’s two most celebrated living poets, and history relates that they were also friends. Unfortunately, little is known of their friendship, and few avenues exist by which to illumine its nature. In Horace's four books of Carmina, three such avenues exist: Odes 1.3, 1.24, and 4.12, and mercantile language is the leitmotif that unites them. Insofar as commercial language pervades these three odes, Horace creates a poetic triptych, a cohesive representation of a relationship cast against the history of Epicureanism. Through a careful reading of these three poems, I elucidate how the mercantile imagery reveals a friendship underpinned by Epicurean philosophy and practice. Horace holds that if we bank on friendship, it will always pay dividends.