Gift to self

 “Tell me, if you buy a gift for someone and that person does not take it, to whom does the gift belong?”

“It would belong to me because I bought the gift.”

The Buddha smiled and said “That is correct. And it is exactly the same with your anger. If you become angry with me and I do not get insulted, than the anger falls back on you. You are the only one who becomes unhappy, not me. All you have done is hurt yourself.”

(ps. it also applies with racial prejudice, religious intolerance, in fact almost all of the things that have their manifestation in some form of anger).