It is explained in the book that it is a sin to kill a mockingbird because they cause no harm. It’s a sin to offend and be inequitable to people who have never caused you or others harm. The novel’s title revolves around this theme to be respectful towards everyone, despite their ways of life that others may not approve of. Society tells you that certain people should act a certain way, and if they do not, then you have the right to disregard and belittle them. But, from this book and these characters, you can learn that everybody is different and has their own limitations. You learn that you should treat everyone fairly and kindly, or else you will be considered the person who is smaller and lesser than