One day Buddha was walking through a village. All of sudden, a very angry and rude young man approached him, called him by names and began insulting him. "You have no right teaching others," he almost shouted, "you are as stupid as everyone else. You are nothing but a fake!"
Buddha was not upset by these insults. Instead he just smiled and replied "tell me, if you buy a gift for someone, and that person does not take it, to whom does the gift belong?"
The man was taken aback by such a strange question thrown back at him. But he regained his rude composure and answered in an obvious brash tone "It would belong to me, because I bought the gift."
The Buddha smiled again, 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, then the anger falls back on you. You are then the only one who becomes unhappy, not me. All you have done is hurt yourself."
Buddha carried his thought forward "Look my friend, if you want to stop hurting yourself, you must get rid of your anger and become loving instead. When you hate others, you yourself become unhappy. But when you love others, everyone is happy."
The young man stood there hypnotized by the saint's presence and his words that ripped the devil in him apart, and the very next moment the transformed man in him gratefully asked "You are right, O Enlightened One, can you please teach me the path of love? I wish to become your follower."
The Buddha answered even more humbly "Of course. I teach anyone who truly wants to learn. Come with me."
I am sure you've got the message: No one can insult you unless you accept the insult on your self.