From the eighth century onward, monastic communities played an increasingly important role in the relief of sinful souls suffering in the cleansing fires of the otherworld. During the reigns of Charlemagne (r. 768–814) and his successors, the abbeys of the Frankish heartland benefited from royal patronage, but they also bore the burden of imperial scrutiny. For the prayers of the monks to be efficacious, Charlemagne believed that all of the abbeys in his realm should embrace a uniform set of ritual practices and adopt a single authoritative code of conduct: the sixth-century Rule of Benedict. Benedict had taught his brethren to cultivate the virtues of obedience, humility, and silence and to avoid all sexual contact in emulation of the angels, whose heavenly ranks they aspired to join in the afterlife. These religious specialists spent their days engaged in lengthy liturgical services, the primary purpose of which was to sing praises to God to beseech his aid for the health of the king and his family, the well-being of the kingdom, and the salvation of all Christians.

The monks’ mastery of their own wills gave their prayers an awesome efficacy, making them important intercessors for the souls of deceased Christians. Over the course of the Middle Ages, untold numbers of people made donations of revenue-producing land and other forms of wealth to cloistered communities in the hope that the prayers of the brethren would ease their suffering in the afterlife. For their part, monastic authors were quick to endorse their own communities as especially proficient in the virtues that gave their prayers the wings to reach the ears of God. Many of them composed ghost stories as a way to promote the power of monastic prayer. Drawing their inspiration from Gregory the Great’s Dialogues, these stories featured spectral visitations of recently dead Christians who described their torments in the otherworld and beseeched the monks to pray on their behalf. A second visit confirmed their release from suffering, providing a valuable endorsement for the monks whose prayers helped to navigate the passage of their souls to heaven.