Joaquim Maria Machado de Assis’s poem “Soneto de Natal” and the chapter “Um soneto” from his novel Dom Casmurro exhibit striking points of intersection that describe the same process: the creation of a sonnet. In the novel, Bentinho abandons his attempt with only a first and last line. “Soneto de Natal” presents a full fourteen; yet, when scrutinized, it rings as hollow as Bentinho’s. This idea of the lacuna speaks to much of Machado’s early poetry, which suggests that access to the poetic muse is bestowed through suffering by experience. Thus, the young Bentinho, not unlike the mute prophet of one such early poem, struggles for inspiration while “Soneto de Natal” presents the inverse: the prophet granted experience who discovers that he is, like a poet-Moses, slow of verse. By analyzing these two sonnets, taking into account their shared imagery, vocabulary, themes, and the stylistic choices of “Soneto de Natal,” we not only find a Machadian critique of the sonnet-mania of the 1890s, but also unmask “Soneto de Natal” as the anti-promethean exemplar of the novel’s sonnet-making blueprint. In a deft sleight of hand, Machado illustrates his point in the most effective way possible: by passing off satire as the genuine article.