As the novel draws closer to its conclusion, Atticus's ultimate faith in human nature causes him to make a mistake that, while an honest mistake, nearly costs him his children's lives. Bob Ewell, humiliated from Atticus's treatment of him at the trial of Tom Robinson, is making veiled, and not-so-veiled threats around town, but Atticus is not fazed, simply instructing Jem to try to understand how Bob might feel, to stand in his shoes, so to speak. Although Aunt Alexandra's constant focus on the differences between her family and others in the community gets wearisome to the reader (and is downright aggravating to Scout and Jem), in this case her assessment of Ewell and his rage is absolutely correct: he will stop at nothing to get revenge on Atticus for taking his "fifteen minutes of fame" and turning it around to make him look foolish--albeit that wouldn't have been hard for anyone to do. Ewell's behavior is in stark contrast to Tom Robinson's; Robinson ultimately pays for his life trying to escape a prison sentence he has incurred for something he didn't do. Tom is one of the "mockingbirds", metaphorically speaking of this novel, Boo Radley being the other. They didn't do anything to hurt anyone, and although Tom was killed, Boo Radley was ultimately spared, although his escape was not from a gunshot, but rather from a fame which he was most unequipped to handle.