What is a summary of Chapter 16 from The Devil's Arithmetic?

Hannah settles into the macabre routine at the camp,
following the nonsensical rules - the "devil's arithmetic" - that Rivka has described
and Gitl has named. So consumed by simply surviving each day, she begins to lose her
memories of her life in New Rochelle. Rivka tells Hannah that the blokova
has a finger cut off every time she loses control over her prisoners. In a
mysterious statement of foreshadowing, she also says that "there are always grown-up
plans" being made.

The commandant arrives unexpectedly at
the camp, and the prisoners begin making clicking noises, warning the children to hide
in the midden. Reuven, who has been at the "hospital" having a scraped knee tended to,
misses the call and is caught by the commandant, who ominously picks him up and says he
should be with his mother. Hannah speaks out that his mother is dead, and the commandant
says ironically that he will make sure the little boy joins her. He takes Reuven, who is
never seen again. That night, the sky is "red and black with the fire and smoke" made by
the burned bodies of an entire new trainload of
newcomers.

Hannah is furious with herself for not having
been able to save Reuven, but Rivka argues that there is nothing she could have done.
Hannah says the Jews have become monsters for allowing this situation but Rivka counters
that they are victims, and that while God is letting it happen, he always has a reason.
Hannah argues that the Jews should "go down fighting," but Rivka, repeating the words of
her mother, says that to endure is much harder, and more heroic, than to "go out
shooting." That night, Fayge, who has not spoken since entering the camp, begins to tell
a story whose message is that the enemy can never enter one's soul, because "(one's)
soul is a part of God" (Chapter 16).