The scene found here depicts two elderly men trying to catch a glimpse of a young woman as she prepares to take a bath. They hide elsewhere in her garden to avoid being seen. This distasteful behaviour is all the worse when considering that they are considered friends of both Susanna and her husband.
Such a display of lust over respect is a common component of biblical tales, attempting to teach us of the importance of discipline and self-control. The artist in this example adds several symbolic items to the scene in order to further strengthen the overall morale story. For example, if you look closely you will see white pearls, silver jewelry, a silk shawl, and a silver jug dotted around the composition.
Susanna was a particularly beautiful young Jewish woman whose husband Joakim had invited the elderly men as guests to their home. They decided to spring upon here once she was alone in the garden and threatened her with consequences if she rejected their advances.