Early medieval religious writers describe powerful and complex somatic and cognitive experiences as astonishment or stupor, drawing on medical discourse. The effects of stupor on the body’s faculties of sensation and movement are described in medical texts, such as English medical writer John of Gaddesden’s (fl. 1305–1348) Rosa medicinae or Rosa anglica (ca. 1313–20), where he reconciles Galen’s and Avicenna’s conflicting definitions of stupor. This note presents a case study of stupor in medieval medical discourse, especially according to Gaddesden, that informs our understanding of narratives about or by medieval anchorites, revealing more complex accounts of physical and spiritual experience.