This panel comes from stained-glass window V25 of Milan Duomo, dedicated to the life of Saint John of Damascus, a leading figure in the history of Byzantine theology, as well as a distinguished doctor in the history of the universal Church. It was offered by the College of Apothecaries (the current Pharmacists) in honour of the patron saint of the guild in the second half of the 15th century. Living in the 7th century and born in Damascus, during the reign of Emperor Leo III the Isaurian, Saint John was unjustly slandered by means of a false letter sent to the Caliph of Damascus, which fell into the trap. Saint John was punished with the severing of his right hand, which was later reattached by the miraculous intervention of the Madonna. He is the patron saint of painters, the disabled (those missing limbs), and pharmacists. Saint John of Damascus is depicted during the torturous severing of his hand: the panel is ascribable to the hands of Pietro da Velate, who began working on some of the Cathedral's stained-glass windows in 1519, amongst these window V25, the work of Niccolò da Varallo.