To Kill A Mockingbird Metaphors

The metaphor, "It is a sin to kill a mockingbird" comes from the book "To Kill a Mockingbird." There are parts in the book where the saying is noticeable and easy to understand. Examples of mockingbirds would be Tom Robinson and Boo Radley, since they have done no harm to anybody. This metaphor does not refer to killing birds but refers to harming people who are helpful, do no harm, and make the world a better place, which these are the reasons it is a sin to kill a mockingbird.
Mockingbirds are not real birds but are depicted as fictionally helpful birds. In today's society, people who have helped with the after effects of hurricane Irma are categorized as mockingbirds, also those who helped with victims of the mass shooting in Las Vegas

and Texas. Not only those, but various tragedies that have happened in the past where people have gone long ways to help the victims are too considered mockingbirds. Any willing person who helps another in a time of need is a mockingbird.
Logically, harming a mockingbird is a sin because a mockingbird does no harm. Referring back to the book, when Bob and Mayella Yule falsely accused Tom Robinson, is another way to understand that harming a mockingbird is wrong. Tom Robinson, being innocent, did nothing wrong, therefore did not deserve what he got. In the book, Tom states how he has always helped Mayella with her house, which when Mayella came on to him, Bob caught them thus outraged.

Mockingbirds make the world a better place naturally by "singing", which also they're supposed to have beautiful voices, although being fictitious. It also plays a part with innocence, for example Jem, Scout, and Dill. They both were innocent at one point until learning how the world really is. When the children were watching the case go down in the courthouse, they saw how racially biased everyone is. Especially how the prosecutor was being horrible to Tom, causing Dill to start crying.