In Live on the Sunset Strip he has a routine in which he describes an incident in which a little voice inside asked him, as he looked on at the mixed group of people he saw in a hotel in Africa, what he saw, and he mentally replied joyfully that he saw all sorts of people of all sorts of colors interacting peacefully with each other. The voice then asked him if he saw any "niggers". He thought, "No," and realized that the word, ordinarily a more regular part of his lexicon, had not even occurred to him in several weeks. "Do you know why?" the voice replied. "Because there aren't any." This caused him to break down into tears. After relating this tale he launches into a moving, persuasive, mostly serious Author Tract about how the word "nigger" and how black people and white people alike should stop using it. It may sound downright cheesy in print, but in context, after all the goofy shit preceding it, the routine hits quite hard.
He stood up for Eddie Murphy, when Murphy was lambasted with criticism about his work being overly profane and racist. Pryor told Murphy, "Look, next time someone talks shit on you like that, you tell 'em to suck my dick."
For added effect, the guy that had told Eddie that his act was too much? Bill Cosby.