If I had to choose one theme of "That Evening Sun," by William Faulkner, I would choose fear. The story explores several kinds of fear that are caused by living in the Old South. Nancy, of course, is afraid of her husband Jesus, who she says has threatened to kill her because she has slept with a white man and is now pregnant. Whether or not this fear is rational is not clear, since Jesus did not threaten Nancy when she first told him of her pregnancy. Nevertheless, her fear is real to her, and she seeks help from the Compsons who have temporarily employed her while their regular maid is out sick.
The Compsons ignore Nancy's fear. Mr. Compson tries to play Nancy's fear down while Mrs. Compson is only concerned about herself. Even though Mr. Compson tries to be sympathetic, he is a weak man, controlled by his hypochondriac wife, who resents any extra time he may spend trying to help the terrified Nancy.
The Compsons are a moderate depiction of the way the white people of the town view blacks. The sheriff views blacks as subhuman, not believing that a black woman could commit suicide unless she was taking drugs.
This tension between whites and blacks causes fear to permeate throughout the town. The blacks are powerless against the whites, but there is no telling when a suppressed man such as Jesus might explode against the whites. The whites nervously overreact to any sign of assertiveness in blacks, as does Mr. Stovall when Nancy demands payment of him. In retaliation he beats her and has her thrown in jail.
The Compson children themselves are afraid. They sense Nancy's fear, and Jason especially becomes afraid of the dark as well, fearing that because he is afraid, that he might be a "nigger" too. In his mind, being afraid is the same as being a "nigger."