The story of the Devil's appearance to St. Dominic in the form of a monkey derives from a medieval legend, according to which the saint seized his tormentor and forced him to hold a lighted candle while he studied. St. Dominic released him only after the candle burned down and singed his fingers.
This candle-illuminated scene is inspired by a famous lost masterpiece of antiquity. Antiphilus of Alexandria's Boy Blowing on a Fire was renowned for its beautifully rendered effects of firelight. Pietro della Vecchia's painting makes deliberate reference to it and to his own celebrated ability to imitate earlier masters.
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