This paper examines medieval discussions of iconography, what an image represents. It concentrates on what Dale Kinney has called narrative etiologies, that is cases where medieval viewers, provoked by an image they did not understand, invent a story that explains it. My examples include the contested reception of ruler portraits, inquiries into images in churches, and narrative elaborations on hagiographical images. These cases demonstrate that medieval viewers were quite happy to accept Pope Gregory the Great's invitation to read images as the literate read texts. For the art historian, they offer gratifying proof that images may provoke verbal narratives instead of merely depending on them.