Persecution of St. John the Evangelist by the Emperor Domitian. As described in the Golden Legend, soldiers shave his head and put him in a pot of boiling oil, but he remains unharmed and free of pain. In the background is a representation of the Porta Latina in Rome, where the event was said to take place. Detail of fresco in the Crypt of St. Magnus (1237), Cattedrale di Santa Maria, Anagni, Lazio, Italy.
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