This sketch is a study for a 3m by 4.20m painting decorating a ceiling at the Jesuit Church in Antwerp, Saint-Charles-Borromeo (now destroyed).  Rubens needs to paint the two Sicilian saints, Saint Lucy, who the executioner must stab at the stake and Saint Agatha, who is bringing the palms of martyrdom. With rare virtuosity, he expresses both the violence of the executioner springing up to avoid burning himself and the saintliness of the Virgin of Syracuse.