Eglon Hendrick van der Neer: Judith, 1678.
This painting came into the possession of the National Gallery through the Salting bequest 1910. They write about it:
The prominence of the figure of Judith, the portrait character of her face, her dress, and the subsidiary position of the maid and the head of Holofernes make it likely that this is a portrait of a young woman in the guise of the Jewish heroine.
Portraits as Judith were popular with female patrons, since this Biblical heroine was considered the epitome of virtue.