This essay examines a literary exchange between the Visigothic poet-king Sisebut (612-621 AD) and his scholar-bishop Isidore of Seville following an anomalous sequence of eclipses. After Sisebut commissioned a scientific treatise from Isidore on such natural phenomena, he responded to the bishop's prose with a short poem on lunar eclipses (De eclipsi lunae). This study interprets the exchange of texts not as a literary game, but as high-stakes political correspondence. It situates the king's verses in an ongoing process of cultural construction in Visigothic Spain, led prominently by Isidore himself, but also tied to a rising ascetic movement. It argues that Sisebut was attuned to Isidore's designs to manage the discourses through which Christian power was proclaimed, and shows how the king attempted to versify in accord with scientific truth so as to fit within Isidore's ascetic intellectual program. This essay examines a literary exchange between the Visigothic poet-king Sisebut (612-621 AD) and his scholar-bishop Isidore of Seville following an anomalous sequence of eclipses. After Sisebut commissioned a scientific treatise from Isidore on such natural phenomena, he responded to the bishop's prose with a short poem on lunar eclipses (De eclipsi lunae). This study interprets the exchange of texts not as a literary game, but as high-stakes political correspondence. It situates the king's verses in an ongoing process of cultural construction in Visigothic Spain, led prominently by Isidore himself, but also tied to a rising ascetic movement. It argues that Sisebut was attuned to Isidore's designs to manage the discourses through which Christian power was proclaimed, and shows how the king attempted to versify in accord with scientific truth so as to fit within Isidore's ascetic intellectual program.