"I'm goin' to git into this war jest as quick as I kin make it." (2.57)—Eb, speaking before war.
"All at oncest I knowed I couldn't stand it no longer, and I jest up and left." (9.65)—Eb, speaking after deserting the war.
Turns out war isn't everything it's cracked up to be. Like Tom, Eb can't wait to get signed up for the war, and despite all the horror and agony he witnesses on the battlefield, Eb keeps his chin up with his best buddy Tom by his side. But as we all know, that doesn't last, and after Tom is dead, Eb feels like "Somehow all the spirit in me has bin gone ever since" (9.87). Cue: Eb's exit from the army.
The thing about Eb's exit (a.k.a. desertion) though, is that he winds up regretting is. Have no fear, Eb, Jethro's here. After our main man finds Eb lurking around the fields, Jethro writes to President Lincoln detailing his predicament. After anxiously awaiting a response, Jethro finally gets a note from Lincoln saying that he's giving all deserters a second chance. Score.
Eb's little storyline has a redemptive message to it. Once he realizes that he was dead wrong about the glory of war and suffers the massive blow of losing Tom, Eb just decides to up and quit. Not only is this a weak move, but now there's a bounty on his head. So it's essentially Lincoln's compassion that saves Eb's hide and gives him a clean slate. When he's finally allowed back in the army, Eb writes home saying, "the blame is mine and Ill take what they say to me and do my job" (10.9). Even though he made a big error in ditching the war, Eb is an adult about it and owns up to his actions—and that's one solid way to right a major wrong.