One of the most important and memorable quotations in the novel, this is spoken by Miss Maudie to Scout in Chapter 10 (page 90 in my old paperback version from 1982). Scout has remembered Atticus's advice to his children about it being okay to shoot tin cans and even blue jays with their new air rifles, but never a mockingbird. It was a "sin to kill a mockingbird," and Maudie explained to Scout that unlike blue jays, mockingbirds were not harmful to humans or their "gardens" and "corncribs." Instead, they only "sing their hearts out" for people to enjoy. The innocence of the mockingbird is extended symbolically to many of the human characters, including Boo Radley, Tom Robinson, and most of the children in the novel.