Lightning sure causes a lot of trouble.
First off, he's a stolen racehorse. He has to be smuggled onto a train and taught how to race. Then he loses his heat and goes and gets himself arrested.
Do you think this horse has any idea of all the ruckus he causes?
But boy, he sure is a thing of beauty, though. As Lucius laments, "Oh yes, I remember him: a three-year-old three-quarters-bred…chestnut gelding, not large, not even sixteen hands, but with the long neck for balance and the laid-back shoulder for speed and the big hocks for drive" (6.28).
Lightning is the opposite of the automobile. In a time when cars were still new, horses ruled the land. Cars were a symbol of modernity, while horses represented yesterday's way of life. Lightning represents a kind of natural beauty and familiarity that is absent from the creaky new technology about to change the entire landscape and way of life of places like rural Mississippi.
At the beginning of the story, Ned suggests that Boss Priest's car is worth the same as the most expensive racehorse in the county. Perhaps this is a bit of foreshadowing, as Ned will wind up trading the car for just such a racehorse.
But Lightning is more than just an average racehorse: his success is the glue holding a lot of people together. He's Boon's ticket to getting his beloved car back. He's Bobo's ticket to getting out of debt. He's Ned's ticket to getting back at Boss Priest for not treating him like family. He's Butch's ticket to seducing Miss Corrie. And he's Lucius's ticket to proving that he is no longer a child.
There's a lot riding on Lightning. Does he deliver on his promise?