The Bodhisatta was once a frog. A water snake out feeding came upon a wicker fish trap and crawled in, expecting an easy meal. But the fish attacked the snake, biting him until he crawled out covered in blood and lay at the river’s edge. Just then, the Bodhisatta took a long leap and accidentally landed in the trap. The snake asked him whether he approved of the fish’s behavior or not. He answered that since the snake ate fish when they went to his place, it was certainly appropriate that they eat him when he went to theirs. Hearing this approval from the Bodhisatta, the fish rushed out of the trap and killed the snake.
In the Lifetime of the Buddha
The snake was an earlier birth of King Ajatasattu. The king was a devoted supporter of Devadatta, a disciple of the Buddha who became his nemesis, and at Devadatta’s insistence, had murdered his own father because he supported the Buddha. Soon after this, King Ajatasattu’s mother, the queen, died of grief. Her brother, King Pasenadi, the righteous ruler of an adjacent realm and a devoted supporter of the Buddha, was full of hatred for King Ajatasattu. King Pasenadi wanted to take back a village that had been part of the dowry given with his sister when she married King Ajatasattu’s father, so he started a war. Whenever King Ajatasattu won a battle, he marched triumphantly back to the capital city; but when he lost a battle, he returned without any fanfare.
When the Buddha heard some of his disciples discussing King Ajatasattu’s behavior after battles, he told them this story so they knew that it was not the first time he had been happy when he won and miserable when he lost.