Today is the feast of Ss. Cyprian and Justina. I've mentioned Cyprian of Antioch before; he's the patron saint of dabblers in the black arts, since according to legend he was a demonologist and necromancer who tried to seduce a Christian girl, Justina, to no avail; she eventually converted him, and they were both martyred in the persecutions under Diocletian. Our historical information about Cyprian is pretty limited. There may well have been a pagan Cyprian at the root of it, because our earliest mentions of the story are fairly close to the time the events were supposed to have happened, but details are muddled because Cyprian of Antioch was early on confused with a more famous and more important Cyprian, St. Cyprian of Carthage.
In any case, it's a good day to read Pedro Calderón de la Barca's classic play, El Mágico prodigioso. It can be found in English translation at Project Gutenberg.