Everything is bigger down South—the houses, the hair, the families. The South is known for big family dynasties, like the Bushes or the Ewings from Dallas. The families themselves are large, and have been for generations. They need those giant old plantation homes just to fit all the people inside.
With big families comes big dysfunction. But as we said, in the South, everything is bigger. Even small families are hugely screwed up—just take the Childers family in Sling Blade. This is a family of three—Mom, Dad, and little Karl, who they keep in a shed behind their house, where he sleeps in a hole in the ground.
After killing one third of his family, Karl is put in a mental hospital. When he gets out, though, he learns that he can choose his family. He's not stuck with the family that stuck him in a hole.
Karl introduces a complex dynamic into Linda's family. Karl sees Frank as a little brother, but Frank sees Karl as a father figure.
Doyle and Karl's father are very different but equally destructive father figures. Karl's dad destroys his own family by ignoring them. Doyle destroys Linda's family by trying to make them a family—without having any clue how to do it right.
Loss of innocence is a complicated thing. It never boils down to one definable moment, like the death of a parent, or losing your virginity, or finding out that Velveeta isn't really cheese—although if all those things happened at once, you'd instantly be an adult, and that would be one of the weirdest days in your life.
Most people lose their innocence by degrees. They can try to stave it off, but that's like putting a finger in a dam. It's going to break at some point, but even if it doesn't, what's the point of saving it?
Sling Blade is a movie about preserving innocence. Salvaging innocence by murdering another person seems like a strange way to go about things, but as we said, innocence is complicated.
Karl is born without innocence, which makes seeing the loss of Frank's innocence even more tragic to him. He hates to see Frank losing something he never had himself.
Both Karl and Doyle are father figures in a way for Frank, but while Karl is determined to preserve Frank's innocence, Doyle seems to be trying to destroy it.
Good friends are hard to find, but who knows how many friendships you've missed out on by writing people off because of their physical appearance, their bad haircuts, or the way they walk or talk?
Oh, well. You live and learn. But some people get it right the first time, like Frank, who is a surprisingly good judge of character for an eleven-year-old. In Sling Blade, he befriends a limping, snarling man with a vicious underbite and a haircut that looks like he did it with his feet. And the two become fast friends, proving that friendship runs deep.
Karl and Frank are good friends because even though they aren't close in age physically, they are close in age mentally and emotionally.
Doyle manipulates his friends, much in the same way he manipulates Linda, instead of winning them by showing them the good parts of his personality, if he has any.
If you were in a certain mood, you could use the Bible to argue against public places of worship. Matthew 6:6 says, "But when you pray, go into your inner room, shut your door, and pray to your Father, who is unseen. And your Father, who sees what is done in secret, will reward you."
In other words, do your praying in private.
In Sling Blade, Karl does just that—he's pretty much the opposite of the televangelist type. Raised on the Bible, Karl has taken his years in solitude to try and figure out what religion truly means to him. Sling Blade isn't a film with an overt religious message, but religion is important to Karl: his view of the Bible and of his Christian faith informs all of his actions. Still waters run deep, and these waters are holy ones.
Karl's father used the Bible—or his own interpretation of it—to manipulate his family. He may fill his house with religious paraphernalia, but does not adhere to the true spirit of his religion.
By interpreting the Bible on his own terms, Karl becomes a Jesus figure of sorts—a person who thinks he is sacrificing himself for the good of someone else, whether that person asks for it or not.
The idea of a mental institutions can conjure up images of tiny cells with padded walls, patients in straightjackets, or people being lobotomized. It's scary stuff, which is why numerous horror movies, video games, and shows—like American Horror Story: Asylum—use it as an element of horror.
But in Sling Blade, the mental hospital is Karl's safe space. It's the outside world that scares him. Agoraphobia is a fear of the environment, but Karl isn't trigged by wide open spaces or Dixie Chicks songs. It's all that freedom and responsibility that frightens him. Paralyzed by an infinite number of choices, Karl feels much more uneasy than he did his freedom was taken away.
Karl seeks confinement, but Frank feels trapped and wants freedom from Doyle.
Karl grew up in a shed, and as an adult, he sleeps in the back of the repair shop or in Linda's garage. Oddly, these places remind of him home and help him feel safe.