Sano di Pietro, The Martyrdom of St. Agatha in an initial D
Tempera and gold leaf on parchment, 10⅜ x 10⅛ in. (26.4 x 25.7 cm.)
Robert Lehmann Collection, Metropolitan Museum
The Metropolitan describes the work as follows: The scene inside the initial D illustrates one of the responses for the Feast of Saint Agatha (February 5): Dum torqueretur beata Agatha in mamilla graviter dixit ad iudicem impie crudelis et dire tyranne ("While blessed Agatha was being cruelly tortured in her breasts, she said to the judge: 'godless, cruel, infamous tyrant.'")
Read more about Saint Agatha.
Source: Website of the Museum