What are four adjectives that describe Atticus Finch?

Atticus is courageous, modest, wise, and perceptive.

Atticus shows his courage in mounting a real defense of Tom Robinson, a black man, despite the contention and danger it causes for his children and for him. He is willing to buck the unwritten racist code of the town to do the right thing. He knows defending Robinson will not be easy, but he does it anyway.

Atticus's children don't know what an expert sharp shooter he is until he has to kill a rabid dog. He is modest in that he doesn't flaunt his achievements and, in particular, doesn't feel a need to be a "macho" man. 

Atticus is wise in picking his battles, and he passes on that wisdom to his children. For example, he counsels Scout to get along with her teacher, who is new to the town, and not to make unnecessary waves in the classroom. Scout begins to learn the lesson of not always having to speak her mind. 

Atticus is perceptive, for instance, in understanding that Calpurnia is a good role model for his children, despite being black. He resists the racism around him and insists that his children show respect to her.