What do you think of Atticus's reaction to Bob Ewell's challenge? Should he have ignored Bob's retaliation or done something else?
Since the first question is an opinion question that the student must make based upon her values, the second question will be addressed with respect to Harper Lee's characterization of Atticus Finch:
Truly, Atticus Finch reacts in character to Bob Ewell's attack. When Ewell, who has reinforced the town's opinion of him as a reprobate by his false accusations of Tom Robinson, crude language, and ignorance, spits tobacco juice in the face of Atticus Finch in retaliation for being proven a man of no integrity and embarrassed--somehow--before those in the courtroom, Atticus reacts by "turning the other cheek" and not lowering himself to the same level as Bob by striking him. For, it is a fight that Ewell wants so that he can, then, feel better about himself when he successfully beats Atticus,
"Too proud to fight, you n****-lovin' bastard?"
Stephanie Crawford, the town gossip, says that Atticus replied, "No, too old."
Later to his children Atticus expresses his basic philosophy again, telling his son to
"...stand in Bob Ewell's shoes minute. I destroyed his last shred of credibility at that trial, if he had any....The man had to have some kind of comeback, his kind always does. So if spitting in my face and threatening me saved Mayella Ewell one extra beating, that's something I'll gladly take. He had to take it out on somebody ....You understand?"
As an attorney, a prestigious position at the time of the novel, Atticus feels he must set an example before the Idler's Club that sits around the courthouse. Therefore, he does not stoop to fighting, and he also does not fall into the trap that Ewell has set for him as he would love to fight Atticus. This behavior is all in character for Atticus.