In Chapter 27, Aunt Alexandra reflects on the attempts of Bob Ewell to break into Judge Taylor's house and to intimidate Helen Robinson,
I know how that kind are about paying off grudges, but I don't understand why he should harbor one--he had his way in court, didn't he?
Atticus explains that Bob Ewell realizes "in his heart" that most people did not believe his and Mayella's "yarns" at the trial. And, instead of being the town hero, he has been again relegated to his dump. In other words, Bob repeats what he has done originally with Tom Robinson: He has attempted to pull down someone else in order to somehow elevate himself and his family. That he has this sort of psychological complex is apparent when Mr. Link Deas comes out of his store after spotting Ewell leaning on his fence. For, Mr. Ewell says to him, "Don't you look at me, Link Deas, like I was dirt. I ain't jumped your---"
Link Deas, who stood up in court to attest to the integrity of Tom Robinson, but was told to sit down, now has his time to say what he would like. He tells Ewell,
"You don't have to touch her, all you have to do is make her afraid, an' if assault ain't enough to keep you locked up awhile, I'll get you in on the Ladies' Law, so get outa my sight! If you don't think I mean it, just bother that girl again."
Now Ewell has not avenged himself at all; instead, he has confirmed the low opinon of him that Maycomb holds for this contentious and vindictive man of reprehensible conduct.