There is some iconography that can only be described as miraculous. Such is the sixth century apse mosaic at the basilica of Saint Apollinare in Classe, five miles from Ravenna, Italy. Such works seem to flash forth, and are never – perhaps can never be – repeated. They delight the beholder immediately but at the same time possess layer upon layer of meaning, which reveal themselves only to the patient. In this article I discuss some of these layers.