This is a world where butchers sing like angels.
This comment sums up the key theme of the novel; it is a world of paradoxes and contradictions and the characters we meet all seem to be a mix of seemingly opposite characteristics and traits that don't seem to go together; this the town drunk was an exceptional citizen and father, the butcher sings like an angel, the motherless child becomes an incredible child and mother. The quote encapsulates both the central theme of the book and also the author's view on life in general.
Alone Fidelis songs old German songs that fill him with shame.
This shows another complexity of Fidelis' character in that he deeply despises the nation that he came from. When the Second World War breaks out it is no longer popular to sing old German songs that previously people found entertaining. Because they remind him of his youth, which was happy, Fidelis still sings them in private but because of the nation that Germany has become he is now ashamed to sing them and ashamed that the nation of his birth has turned into the nation his adopted country is at war with. He is also ashamed that Tante has chosen to align herself with the German regime and to turn two of his American sons against both their country and their family by takin them back to Germany.
These things happened with such regularity that Delphine developed a nervous twitch on her brain; a knee-jerk response that rejected hope and light.
This description of Delphine illustrates the way in which life and hardship have beaten her down without her being fully aware of the fact. She is accustomed to disaster and tragedy and disappointment and has learned not to hope or to see a light at the end of the tunnel, which she feels mitigated the pain she will feel. If she expects darkness and gloom then it cannot hurt her with its surprise. It also demonstrates that whilst on the surface she seems happy in her way she is actually rather depressed and beaten inside.
A stocky Polish girl from off a scrap of farm is not supposed to attract men so easily, but Delphine was compelling. Her mind was quick - too quick, maybe."
This description of Delphine shows that she had already gone further than her heritage would suggest she might and also infers that it is her mind in combination with her looks, rather than her looks alone, that are the attraction. From this we can also infer that she was very smart, and likely to be able to read men very well which enabled her to be exactly what they wanted thus making her "compelling".
