Many of Pietro Rotari’s portraits show buxom women with suggestive looks on their faces. La Penitente is a young girl who is either ashamed of something she has done or seen. Her face is down cast as if in humble prayer or deference, while her fashionable dress seems a bit too large for one so young, with an unnecessarily plunging neckline.
At first glance, her situation seems innocent enough, however, on the table next to her sits a book, presumably the Bible, with pages held by a whip. There were many Catholic orders through out Europe and Americas that adhered to doctrines of corporal penance or voluntary flagellation which means, they whip themselves for God.
If you commit a very serious sin, then you have to work it off in the form of penance. It is unclear what manner of sin this young girl would be capable of to deserve such a severe punishment.