A story that always sticks to me, that my grandfather used to tell me many times: Once Buddha was passing through a village and during his stay there he was giving a talk to the locals. During this talk, a local ascetic got very upset. He was upset as people had started listening to and following Buddha instead of him.
He got so angry that one day he came and spit on buddha’s face and started shouting. At this Buddha simply smiled. Buddha’s followers and local leaders were upset and wanted to take revenge. But Buddha stopped them saying that it was between him and the ascetic, they didnt need to do anything, and calmed them to wait.
The ascetic went home but could not sleep. Next day he came back and bowed to Buddha’s feet and said, who are you ? what have you done to me ? At this Buddha replied, I havent done anything, All I did was to not accept your negative energy when you were angry. By not accepting it, the negative energy stayed with you.
Grandfather used to end it with analogy, If I have 10 dollars and I offer them to you, but you say No thanks! then who has the 10 dollars ? I do. But if you accept the 10 dollars add to it and give them back to me then the cycle continues…
Similarly, Anger is a like a coal, a burning coal. First it burns the person who has it, then they throw it others. If the other person accepts it, it burns them. They take it add fire to it, and then throw it back …. and cycle continues.