John Mirk, Augustinian canon of Lilleshall Abbey, was one of the most widely read and influential religious writers in fifteenth-century England. Mirk's first readership early in that century certainly consisted of his fellow clergy. By the late fifteenth century, however, Mirk's Festial (circa 1382-1390) was regularly published and reissued in new editions for a much wider audience. This Middle English collection of sermons, originally intended as an anthology for use by poorly equipped priests, was adopted for private reading by the merchant class and aristocracy, whose tastes favored devotional writing in their vernacular tongue. Within its first one hundred years the Festial found a general public hungry for its blend of sacred but fascinating topics: biographies, brief histories of holiday origins and doctrines, stories infused with shocking behaviors and supernatural events, and local legends.

The Instructions for Parish Priests (circa 1382-1390) is a basic how-to manual aimed at...