explain atticus reactionto mr. ewells threat. what dose it shows about atticus character ?

I love the character of Atticus. Atticus's dry humour is enough to make Ewell quiet down. When Ewell charges Atticus with being a "nigger Lover" and he is afraid fighting in the "obscure" war, Atticus simply replies that he is too old. Atticus gently explains to Jem and Scout that Ewell has nothing left. He is more of a social Peoria now than ever. Vague threats and accusations are all he has left to save face with. Atticus isn't so much sorry for Bob rather than the pathetic situation this “human being” has put himself in.