"I hope and pray I can get Jem and Scout through it without bitterness, and most of all, without catching Maycomb's usual disease. Why reasonable people go stark raving mad when anything involving a Negro comes up, is something I don't pretend to understand" (88).
The above passage quotes Atticus talking with his younger brother Jack about the Tom Robinson case. What he means by "Maycomb's usual disease" is racism. Atticus is appointed by Judge Taylor to take Tom Robinson's case, but he doesn't have to care about it, and he sure doesn't have to prepare a strong defense--but he does. This shows that Atticus is against all of the prejudice and discrimination against blacks in his community. When Atticus discusses with Scout about the reasons why he has taken the case in chapter 11, he says the following:
". . . well, all I can say is, when you and Jem are grown, maybe you'll look back on this with some compassion and some feeling that I didn't let you down. This case, Tom Robinson's case, is something that goes to the essence of man's conscience--Scout, I couldn't go to church and worship God if I didn't try to help that man" (104).
What Atticus is saying in this passage is that he is greatly concerned about what this trial represents and what the fight really is about. He understands how racist his community is, but he knows that he needs to take the opportunity to stand up against it by doing his best in the Tom Robinson case. He also knows that the odds are stacked against him and Tom, but if he doesn't put up a good fight, then he would only be as good as those who perpetuate the racial problem. Not only that, but he wants to be a good example for what's right to his children. He doesn't want them to grow up racist either.