In January 1786, the Spanish Inquisition accused the Mexican theologian and bibliographer José Mariano de Beristain of purchasing, possessing, and reading aloud the French pornographic novel Le Portier des Chartreux (The Porter of the Charter House). Flouting his vows, the clergyman had invited men and women to his bedroom, read them the novel, and showed its illustrations. Beristain's story offers a rare glimpse into readership practices and the transmission of ideas in the eighteenth-century Spanish world. Le Portier was not just pornographic; it also had a philosophical and political message that, according to current scholarship, instilled radical ideas in readers. Beristain's story, however, shows that instead of absorbing the intended message, readers either were scandalized or simply took pleasure in the pornographic elements of the story. Their understanding of Le Portier thus challenges the idea that “politically motivated pornography” directly affected public opinion in the late eighteenth century.