Quote 40
In front of him, he read from the copy of Mein Kampf. His savior. Sweat was swimming out of his hands. Fingermarks clutched the book. (26.2)
Max knows that if he can "pass" as a non Jew long enough, he can get to Himmel Street, his best change for survival. The very best way to establish this identity temporarily is to carry a copy of Hitler's book.
Quote 41
In sloppy lettering, the words JEWISH FILTH were spilling over at their edges. (29.75)
Hans gets into trouble for painting over the slur. Such slurs, painted across Jewish homes, shops, synagogues, were part of the campaign to identify Jewish people as subhuman.
Quote 42
They were French, they were Jews, and they were you. (52.18)
Death is talking about the death of a group of French Jews murdered in a Polish prison. He's reminding us that we are all human, all united by Death. It's ridiculous to kill another human, when the job will be done on its own in due time.