Jem shows his respect and admiration for his father throughout To Kill a Mockingbird. One example comes when Jem lost his pants on the Radley fence in Chapter 6. Jem decided to make the dangerous trip back to the Radleys in the middle of the night to retrieve them. Scout wanted him to just leave them there. But Jem explains to Scout that he must get them back so that Atticus doesn't find out that they have lied to him. He knows he'll be in trouble with Atticus, but he also knows he will have lost his father's trust.
"I--it's like this Scout," he muttered. "Atticus ain't ever whipped me since I can remember. I wanta keep it that way... We shouldn'a done that tonight, Scout."
Another example comes when Jem discovers that Atticus's old nickname was "One-Shot" Finch--the deadest shot in the county. As unbelievable as this fact was, Jem was even more astounded that Atticus had never told him about it before. It was his first lesson in humility. He told Scout not to tell any of their schoolmates about it.
"I reckon if he'd wanted us to know it, he'da told us. If he was proud of it, he'da told us...
"Naw, Scout, it's something you wouldn't understand... Atticus is a gentlman, just like me!"
Perhaps the best example is when Jem stands by his father the night that the lynch mob surrounds Atticus at the jail. Jem didn't quite understand what was happening, but he sensed that Atticus was in danger. He could tell that Atticus' didn't have a chance against the group of men, but he understood that his father was making a stand for some important reason. And Jem's youthful allegiance wasn't lost on Atticus.
As they passed under a streetlight Atticus reached out and massaged Jem's hair, his one gesture of affection.