In 1141, a land octopus living in the spandrels of the convent of Disibodenberg, in Germany, visited Hildegard von Bingen, the new head nun, and gave her visions, most likely via a combination of chromatophoric signals and pressure phosphenes from palpation of her eyeballs.
Being as she was steeped in her religion, and with the obvious cross-species language difficulties, she misinterpreted the octopus' attempt at communication as messages from the "voice of heaven". She recorded her theological interpretations of these visions in her book, Scivias ("know the ways"), which included the above illumination in the frontispiece.
Unlike later illustrations of her receiving the visions, which show divine light-rays from the sky as would suit the presumptions of the time, this original one was either done by her or made from her sketches. In fact, the image shows her sketching on a wax tablet, perhaps recording the event as it happened. So it's the most accurate depiction of the encounter -- one clearly more cephalopodic than theophanic.
(Thanks to reader Rich Thomas for bringing this to my attention.)