Ten-year-old Sarty is the extraordinary hero of "Barn Burning." Sarty's father forces him to help burn barns, and lie about it afterwards. Yet this boy has a distinct sense of justice. He might have developed this from spending so much time in courtrooms, and listening to the proceedings. When we first meet Sarty, we can assume that this wasn't the first time Abner was called to court, though we don't know if Sarty has testified before.
This sense of justice functions as a moral code that tells him: 1) barn burning isn't nice, and 2) it's wrong for his father to make him lie about it and participate in it. He knows that if he helps his father burn barns, or lies about it, he is also guilty. (His sense of guilt is compounded by the fact that he inherently knows that barn burning is inherently wrong.) We aren't talking about legally or religiously wrong, because Sarty doesn't necessarily see things in those terms. Sarty does seem, however, to have a strong sense of civic duty, or duty to his community.
For example, think of the scene where Abner tells Lennie to hold Sarty. He threatens to hit her if she doesn't let him go. We can assume Sarty knows that hitting his mother is wrong. But, in his mind, not doing everything he can to save the de Spain barn is even worse. Likewise, he would prefer not to have to betray his father and break his mother's heart, but he also knows he can make his own decisions. We also have to remember that Sarty is ten, and that he is in a position no child should have to be in. Faulkner has certainly loaded him down with complexity.
We know that seeing the de Spain mansion is an important moment in Sarty's life because we get a big chunk of Sarty's thoughts. It's as if the mansion wakes him from a daze. Interestingly, the first thing the mansion reminds him of is "a courthouse" (41). This suggests that Sarty has not only seen a real courthouse, but also that he has some positive feelings about the legal system, which his father is so adept at thwarting. The mansion gives Sarty a sense of "peace and dignity" (41). In Sarty's experience the legal process of justice is messy and unfair and has little to do with peace and dignity.
That's OK, because, according to him, the de Spains don' need the legal system. Sarty thinks the mansion will shield the de Spain barn from being burned. Not only that, but the sight of the mansion might even change his father so that he doesn't even want to burn barns anymore. That gets more to the heart of the matter. Sarty doesn't understand that the southern mansion was probably built on activities worse than barn burning, but he knows it wasn't built by living the way his father lives. Unlike anything he's ever seen, the mansion represents an extreme alternative to his father's way of life.
Sarty's reaction paints him as naïve. Even as he watches his deliberately father track horse poop on the de Spain's white rug, destroying all that "peace and dignity" with one move, he holds out hope.
Still, when Sarty sees his father treated with contempt by de Spain, he realizes that maybe there is more to the mansion than meets the eye. This growing awareness allows Sarty to sympathize with his father, at least for a time. The experience of living by the de Spain's mansion is a positive experience, event though Sarty's idealization of the mansion ultimately vanishes. It reminds him that there are many alternatives in between the two-room shack and the mansion, and thus gives him reason to hope.
We've already discussed some of Sarty's changes in terms of his experience with the de Spain mansion. Over the six days of the story Sarty undergoes other changes as well. For example, when we first meet Sarty he's scared and hungry. He doesn't want to lie for his father, but he's going to do it. Why? Because he sees the Justice and Harris as "Enemy! Enemy!," to put it bluntly (10). As is made clear in paragraph 4, he believes that his father's enemies are his enemies as well.
Imagine what it must have felt like to have his father accuse him of planning to not lie, then hit him, and then give him a lecture about being loyal to your family. As we learn when Sarty follows his father to the de Spain mansion, the child finds his father "outrageous," unreasonable, and unfair (40). After his father's speech, Sarty wants to run away, but something holds him back.
Now, we've already discussed how seeing the de Spain mansion is a turning point for Sarty, because it represents the chance of a better home and life. Another turning point is when de Spain complains that the rug hasn't been properly cleaned. It seems like only a ten-year-old would find de Spain unfair. Sarty knows his sisters put time and effort into cleaning it. And he knows that the 1,120 pounds of corn de Spain is charging them will be on his back to pick and haul. If he was aware that his father knew he was ruining the rug when he first stepped on it, Sarty might feel differently. But, as things stand, in Sarty's mind de Spain becomes an even more "outrageous" figure than his father. As a result, Sarty seems to get over being mad at his dad and the two seem to have achieved a rough harmony.
The final pivotal moment that we'll discuss here happens when Sarty's father asks him to get oil for him, obviously to burn down the de Spain barn. At that moment, when Sarty is in the act of getting the oil and becoming his father's accomplice, he imagines running away and never having "to see [Abner's] face again" (89). Interestingly, he feels that he "can't" (89).
Given that Sarty does run away at the end of "Barn Burning," we wonder what exactly turns Sarty's can't into a can. Maybe it's when he realizes that his father and brother know he doesn't want them to burn down the barn, but are going to do it anyway. Once again, his wishes are brushed aside as unimportant. To overcome "the terrible handicap of being young" (40), Sarty, over a series of intense movements, makes his presence felt in the world. He does what he thinks is right, and what he wants to do. Since he's only ten, this choice will surely have its hard repercussions. The idea of him out in the world alone is disturbing. This tension between the super tough Sarty who acts like a mature adult, and the vulnerable, skinny, hungry Sarty who needs love and care is part of what makes this character so compelling.