In The Boy in the Striped Pajamas by John Boyne, there are a couple of quotes in the novel that give meaning to the phrase “to turn a blind eye.” Two incidents come to mind, both involving the concentration camp prisoner Pavel. The second incident alerts Bruno to the need to turn a blind eye at Auschwitz because even he, the son of the camp commandant, needs to "to keep his mouth shut and cause no chaos at all."
In the first situation, Bruno has fallen off the swing that hangs in the yard of his home at Auschwitz. He has scraped his knee badly, and Pavel cleans it up. When Pavel tells Bruno that he is a doctor, Bruno is quite surprised. Bruno says, “But you're a waiter," he said slowly. "And you peel the vegetables for dinner. How can you be a doctor too?” At this moment, Bruno’s mother enters the kitchen and “looked distinctly uncomfortable.”
As Bruno leaves to go to his room, he overhears his “Mother saying thank you to Pavel” and then adding, “If the Commandant asks, we'll say that I cleaned Bruno up.”
Bruno does not understand why his mother would want to take credit for something that Pavel had done. Bruno does not realize that his father would be extremely angry to learn that a Jewish prisoner had provided medical attention to his son. Bruno’s mother recognizes Pavel’s kindness in tending to Bruno’s wound and also recognizes that this would make her husband angry. However, the fact that she will not say anything to her husband is very much her way of turning a blind eye to the situation at Auschwitz. In fact, the many incidents that require her to turn a blind eye at Auschwitz make her uncomfortable, and she ultimately prevails on her husband to agree that she and the children can return to Berlin.
Then, when Pavel is serving the commandant and his guests, his hands "were shaking slightly under the weight of” the dishes, and when Pavel turns to refill Lieutenant Kotler's glass, the bottle falls and spills the wine onto Lieutenant Kotler's lap.
What happened then was both unexpected and extremely unpleasant. Lieutenant Kotler grew very angry with Pavel and no one—not Bruno, not Gretel, not Mother and not even Father—stepped in to stop him doing what he did next, even though none of them could watch. Even though it made Bruno cry and Gretel grow pale.
It is clear that Lieutenant Kotler got so angry at Pavel that he struck him, probably repeatedly, and no one at the dining room table intervened. Bruno realizes that,
if that was the kind of thing that went on at Out-With then he'd better not disagree with anyone any more about anything; in fact he would do well to keep his mouth shut and cause no chaos at all. Some people might not like it.
This is the ultimate quote in the book that signifies the importance of turning a blind eye.