The story of the suffer you gave to other, will return to you eventually.

Once upon a time, there was a hunter who had 32 fierce dogs help him hunting the animal. One day he went inside the woods and saw a monk. He think this would bring bad day for him. That day, he could not find any single animal and was very angry.
In the evening, he saw the monk resting beside the tree. He wants to punish the monk for brought him bad luck. He orders his dogs to attack to monk. The monk fled and climped up a tree. All the dogs were barking and waiting for the monk to come down. The hunter uses a sharpened wooden stick, stabbing the monk's foot, try to make him fall down. But the monk's robe fall to the hunter and covering all of the hunter's body. All the dogs thought the monk was fell down so they all attack to hunter who is under the monk's robe. Not long after that, the hunter was dead only the bone left under the tree. And all the dogs were gone and the monk came down from the tree safety. This is the meaning of "The suffer you gave to other, will return to you eventually." or doing good deed make you good, doing bad thing make you bad.

It is like a boomerang, it will return to you in the end. But not only do bad thing to other, you must learn how to share your happiness to other too.