The Middle Ages are not usually considered an era when the law was friendly to laborers. Numerous regulations in medieval England were very unfriendly to them. However, religious laws—that is, canon law—did act to protect laborers when it came to working on holy days. Examining cases in the ecclesiastical courts, this article traces discussions concerning who was to blame, from theory into practice, when masters compelled their subordinates to work on holy days. Differing ideas on how to assign blame were ultimately reflected in the ecclesiastical courts. Some courts prosecuted only masters, while others prosecuted both masters and subordinates.