Although Jem loved his father deeply, he had never been very impressed with his skills, especially since Atticus was "too old" to play football, Jem's passion. Jem thought he knew all there was to know about his father, until the day Atticus took down the rabid dog with one shot in a very dangerous situation. After Atticus killed the dog, Jem was reduced to a state of "numb confusion." When he could finally speak, he remained in awe of what he has just witnessed:
'd you see him, Scout? 'd you see him just standin' there? . . . 'n' all of a sudden he just relaxed all over, an' it looked like that gun was a part of him . . . an' he did it so quick, like . . . I hafta aim for ten minutes 'fore I can hit somethin' . . . .
Jem was further amazed that Atticus never shared the fact that he was known as "Ol' One-Shot" when he was a boy; he also wondered why his father did not hunt. It is Miss Maudie who explained to Jem that Atticus took no personal pride in his skill because it was a gift and that he would not hunt because he felt he had "an unfair advantage over most living things." Scout could not wait to go to school and let everyone know that her daddy was "the deadest shot in Maycomb County," but Jem told her to say nothing. He understood his father's character in a new way.
Jem's respect for Atticus had deepened immensely, not because his father was a good shot, but because he did not need to brag about it or capitalize upon it. Also, in watching Atticus face the rabid dog, Jem saw a type of courage in his father that he had not known existed. Jem's perception of Atticus became much truer; his father was a man of unusual character and courage. This change in Jem's attitude is shown clearly in the conclusion of Chapter 10:
Atticus is real old, but I wouldn't care if he couldn't do anything--I wouldn't care if he couldn't do a blessed thing . . . . Atticus is a gentleman, just like me!
Jem is filled with joy by what he has discovered about his father.