When the Bundren's reach Jefferson, Mississippi, on their journey to bury Addie Bundren in her hometown, they have been carrying the coffin that holds Addie's body for seven days. Within these seven days, the body deteriorates and produces an extremely revulting smell; the body has been emerged in a river, soaked by rain, left in the heat, and nearly burnt in the barn fire along with the general smell of rot of decaying flesh.
This smell is so grotesque that as the family heads into town, two men state: "Great God...what they got in that wagon?" Jewel's character is already hot-tempered and devoted to his mother, so any comment that denegrates her standing will instigate his harsh retaliation, and as a result, Jewel responds: "Sons of b*****." But as he is saying this, the wagon has moved passed the speakers to the leading white man who pauses, is obviously extremely offended, and threatens to kill Jewel. Jewel is eager to fight with the man, but Anse, Darl, and Dewey Dell try to hold him back and get him to apologize.
The constant repitition of "son of a b****", first at Jewel to Darl, now Jewel to the others, shows the contrast between how Jewel feels about his mother versus women in general. The argument with the white man is yet another depiciton of town people versus country people. As a combination, the town people are more savvy and will always end up taking advantage of the country people, thus, inadvertently, Jewel is working out his own mother issues -- knowing that he is different than his family, Darl knowing that Jewel's mother is a "horse" (Jewel being the product of Addie's infidelity) -- and the town hurting the country again by insulting Jewel's mother.