Old Isaac McCaslin heard this story, relating events that took place before he was born, from his older cousin, McCaslin Edmonds, who was 16 years his senior and like a father to him: A young child, McCaslin Edmonds rides with his Uncle Buck to the neighboring plantation of Hubert Beauchamp, in pursuit of an escaped slave. The slave, Tomey's Turl, runs away frequently to visit Tennie, a slave of the Beauchamp's with whom he is in love. Tomey's Turl eludes McCaslin and Uncle Buck, who are forced to rely on the leisurely Hubert Beauchamp for help. They are forced to eat dinner with Beauchamp and his sister Sophonsiba, who is looking for a husband and has Uncle Buck in mind. Hubert and Buck search through the woods for Turl and make a 500-dollar bet over whether he will be caught outside Tennie's cabin that night. That night he is indeed at the cabin, but he runs past them and eludes capture. Buck and young McCaslin are forced to spend the night at the plantation house.
Buck and the boy accidentally go into the wrong bedroom and discover Sophonsiba lying in the bed. She wakes up and screams, and Beauchamp takes advantage of the situation to try to pressure Buck to marry Sophonsiba. Buck rejects the idea angrily, and the two men play cards to settle things: a single hand of poker will decide whether Buck will have to marry Sophonsiba and also who has to buy the other's slave, since the situation with Tennie and Tomey's Turl is clearly unmanageable as it is. Buck loses the hand and sends McCaslin home to fetch Buck's twin brother, Buddy, a legendary poker player. Buddy arrives and coaxes Beauchamp into another poker game. They spend a great deal of time hammering out the stakes, but in the end, Beauchamp folds, and Buddy wins the game. Uncle Buck, Uncle Buddy, McCaslin, Tennie, and Tomey's Turl return to the McCaslin plantation—Tennie and Tomey's Turl will be married.
Faulkner's technique in Go Down, Moses is to present stories whose full significance in the overall history of his characters is not apparent until later in the book. The book explores the history and development of the McCaslin family, which is descended from Carothers McCaslin and occupies the plantation he founded. Faulkner incorporates into the McCaslin family many of the characteristics he viewed as essential to an understanding of the South as a whole, including the painful racial divide between whites and blacks that defined Southern history in the decades before and after the Civil War. He does this by splitting the McCaslin family tree into two branches, one white and the other black. The white branch, obviously, descends from Carothers McCaslin and his wife; the black branch descends from Carothers McCaslin and the slave-girl Tomey, with whom McCaslin had a sexual affair.
"Was," which appears at first to be simply an innocuous and amusing story (if one historically appalling in its treatment of blacks and women as things to be gambled over) about the marital maneuverings between a spinster and an affirmed bachelor, is actually the story of the origin of the black branch of the McCaslin family tree. Tomey's Turl is Carothers McCaslin's son, Buck and Buddy's half-brother. Turl and his wife, Tennie, will continue the black McCaslin branch into the future.
On its own terms, "Was" is a brilliant set-piece, a probing look at the past and a handy opportunity for Faulkner to establish some of the important McCaslins—Buck and Buddy, the old bachelor twins, and the young McCaslin Edmonds. With the brief introduction to the story, Faulkner also creates a presence for old Isaac McCaslin and indicates a distant future in which this story is simply a memory of something overheard, a "was" instead of an "is." Isaac McCaslin will prove to be the central character in Go Down, Moses, and Faulkner helps build his stature in the reader's mind by introducing him in advance in the first two stories of the book.