It was a clear, sunny day. The weather was beautiful.
The Buddha was walking through a forest when he saw a huge eagle chasing a dove. Just as the eagle was about to swoop down and catch it, the dove spotted the Buddha and went to his side for safety. The Buddha protected it from the eagle. The eagle perched on a nearby branch and said, "You can save the dove,but that means you're starving me. You're really mean."
The Buddha kindly said, "Tell me what you want to eat, and I'll get it for you."
The eagle replied, "I eat meat."
The Buddha took out a knife and cut a piece of meat from the flesh of his own arm. He gave it to the eagle, but the eagle complained, "There's more meat on a dove than that," so the Buddha sliced off another piece from his arm, but he was getting down to the bone where there's not much meat. Finally he had cut all the meat off his arm, but there still wasn't as much as the weight of the dove.
The eagle asked the Buddha, "Are you sorry you've ruined your own arm?"
The Buddha answered, "I am not in the least bit sorry. My mission is to save all living things. What difference does a bit of flesh off my arm make?
The eagle sneered, "You're just saying that to sound good."
The Buddha said, "If my words are the sincere truth, may my arm grow back as good as new." When the Buddha made this oath, the flesh on his arm did grow back, just like new.
When the eagle saw this, he flew up into the sky and revealed his true shape: he was the Emperor of Heaven! He had heard that the Buddha was kind,so he had come to test him. He showed his deepest respect to the Buddha and then flew away, singing great praises for the Buddha's mercy.
Before long, everyone knew that the Buddha had cut away his own arm in order to save a dove.（From The Story About Free Captive Animals)