“I examined every pore in front of the steamed-up mirror: face, hands, feet, ears—everything—to see if there was any trace of impurity left. I wanted to know who was the dirty one now.” 

Hannah, Leo, and their families are often called “dirty” or “filthy” by Berliners who are more “Aryan.” In this scene, Hannah was called “dirty” by a neighbor and is trying to scrape away all of her “impurities” in both a literal and figurative sense. By cleaning herself so thoroughly, she reasons her neighbor must now be the “dirty” one by comparison.

“She converted her bedroom into her refuge, keeping the window overlooking the interior courtyard always closed. In dreams, I would see her falling fast asleep from the pills she took before going to bed, engulfed by her gray sheets and pillows.” 

Both Anna and Hannah’s mothers use their bedrooms as refuges from the world. Rather than face their challenging situations, they are passive and spend much time dwelling on the past.

“Sometimes the Ogre used to see us and shout insultingly ‘the word beginning with J’ that Leo and I refused to pronounce. As Mama insisted, we were Germans first and foremost.” 

This passage points to a central crux of the novel. The ‘word beginning with J’ is presumably “Jewish.” Hannah refuses to use this word because she feels it is important to reclaim her identity as a German. Although she is not ashamed of being Jewish, she does not want to reduce herself to others’ categories of classification.