Christmas prepares to sneak out of the McEacherns' house, and realizes that Mr. McEachern has found his secret new suit. He puts it on and goes down the road to meet a car. When Christmas goes into town with Mr. McEachern, who must meet his lawyer, he first meets Bobbie, the woman he is sneaking out to see. The meeting takes longer than expected, and so McEachern and Christmas must get lunch in town. McEachern's stinginess leads them to a small and dingy-looking restaurant, where Christmas falls for their waitress Bobbie, even though he expects never to see her again.
Six months later, McEachern goes back into town to see his lawyer and again brings Christmas, this time giving him a dime to spend while McEachern is in the meeting. Christmas goes immediately back to Bobbie's restaurant. He orders coffee and pie, not realizing that he does not have enough money to pay for them both until Bobbie has already served him. She understands and takes the coffee back, but her boss notices and berates her. Christmas is so ashamed that he avoids going back to town for months, instead working hard on McEachern's farm. McEachern notices, and as a reward gives him the heifer that he later sells for spending money to use on Bobbie. The next week Christmas goes back to town for the first time with a half dollar that Mrs. McEachern gave him. He goes to the restaurant to try to repay Bobbie for the coffee, but she is not there and the owner laughs at him. He runs into her outside, and she is thankful. They agree to meet a few days later, and Christmas sneaks out and runs the whole five miles to town to meet her. When she arrives, she tries to tell him without saying it explicitly that she can't sleep with him because she is menstruating. He does not catch on because he is a virgin. She eventually realizes this and explains her situation to him. In response, he strikes her and walks quickly away. Christmas starts regularly sneaking out to see Bobbie and stealing money from Mrs. McEachern's secret stash to buy her things.
Max complains to Bobbie that she is spending so much time with someone so poor, but Bobbie says that she is doing it on her own time, she likes him, and he pays her anyway, although both Max and Mame know that if he is paying her it must only be small change. One night after sleeping together Christmas tells Bobbie that he believes he is part black, but she tells him he is lying, and he does not force the issue. Christmas doesn't know that Bobbie is a prostitute, and he believes that he is the only man who has ever been to her room with her. When he walks to her house one night and realizes that there is a man in her room with her, he leaves and does not come back for two weeks. Upon his return, he hits her. After that, Bobbie explains to Christmas that she is a prostitute, telling him that she thought he already knew. He starts smoking and drinking regularly, hanging out at the restaurant with Max, Mame, and the other customers. He even takes Bobbie to country dances, a fact that he is careful to keep hidden from McEachern. During the day he still manages to work hard enough to keep McEachern as satisfied as possible.
McEachern eventually figures out that Christmas has been wearing the suit that he bought secretly. He knows he must be wearing it at night for lecherous purposes. As he contemplates this he sees Christmas slip down his rope past his window, and follows him outside. With seeming clairvoyance McEachern, now on his horse, knows exactly where to go to find Christmas. He enters the school to find a dance underway and goes straight to Christmas and Bobbie, shouting at Bobbie to get away from his son. He starts to attack Christmas, who smashes a chair over McEachern's head, killing him.
Bobbie starts screaming and runs to her car, beating Christmas when he approaches her. Christmas does not seem to notice, telling her that he will meet her later. He goes to the horse that McEachern left outside. He stops at the house to take the rest of Mrs. McEachern's money, and then rides the horse towards town until it becomes so exhausted that it refuses to go on. He runs the rest of the way to Max and Mame's house, where he finds Bobbie in her room with a stranger. He shows her the money he has brought for them to escape with, but she attacks him, incensed that he has gotten her into such a dire situation. Christmas does not seem to understand anything that is happening. The stranger knocks him down and punches him a few times. Finally, the stranger and Bobbie leave to go back to Memphis, leaving Christmas lying on the floor, conscious but unmoving.
The eighth and ninth chapters of Light In August develop more fully the theme of the connections between sexuality, race, and violence that defines Joe Christmas's life. In these chapters Christmas finally loses his virginity, and he also commits his first murder. These two firsts are not unconnected. Christmas himself claims to have killed McEachern for Bobbie, which is probably true considering that until that fatal moment, Christmas had always accepted beatings from McEachern; it is only when Bobbie becomes involved that Christmas's rage becomes murderous. Christmas's violence, however, is not used solely to protect Bobbie. He uses violence against her multiple times, first as a reaction to her explanation of menstruation, and then later when he realizes he is not her only lover. His feelings for her are complex and contradictory. He is disgusted by the idea of menstruation, picturing a beautiful urn corrupted by a vile dark liquid. This speaks to his inherent desire to see women as pure, even though he wants to have intercourse with them.
His violence towards the first prostitute also shows his inherent distaste for sexualized women. This issue becomes more complicated with the arrival of Bobbie, upon whom he projects a false purity, and yet from whose impurity he benefits. The difference between Christmas's reactions to these two prostitutes also exemplifies the importance of race in these chapters. He beats the black prostitute brutally, while his violence against Bobbie is far more subdued, and is always removed from their sexual encounters. With the first prostitute he essentially uses violence to replace sex, while with Bobbie violence is only an adjunct to their sexual relationship. These varying uses of violence with prostitutes of different races seem to highlight Christmas's own feeling that his blackness deserves punishment. His need to tell others that he is black when even he does not know that it is true arises again in these two chapters, when he tells Bobbie that he is black. His desire to proclaim his racial identity shows how conflicted he is about it himself. He tells Bobbie that he is black in a boastful way, and yet it is as if he is seeking punishment for this fact. He seems both proud and ashamed of his racial makeup...but most of all deeply confused.
These chapters also take a critical look at fundamentalist religions. McEachern, although a murder victim, is not at all a sympathetic character. Faulkner derides his fundamental Presbyterianism, creating a character who has sapped all of the life energy out of his wife and has beaten his adopted son into a hard murderer. The narrator seems most disgusted with McEachern's absolute certainty about his own moral righteousness, and makes even a misogynistic murderer like Christmas somehow sympathetic.