The Bodhisatta was once a tree fairy and he lived near a famous brahmin priest. When it was time to offer a Feast for the Dead, the priest had his students take a goat down to the river to bathe and groom him and feed him a final meal. Nearing death, the goat became aware of his past lives and broke out in joyous laughter, but then the laughter turned to tears. The students asked the goat why he both laughed and cried, and he told them he would answer this question in front of their master.
When they brought the goat to the brahmin priest, he explained that he had once been a brahmin priest who sacrificed a goat for a Feast of the Dead, and his punishment for killing that single goat was five hundred births that all ended with his head being cut off. This was going to be his last beheading, so the laughter was because his impending death would free him from misery. And he wept wails of compassion because he realized that the priest was now going to suffer a similar karmic fate after killing him. When the priest heard the story, he decided not to kill the goat and would follow him around to protect him from others, but the goat said no matter what the priest did, there was no escaping his fate. Shortly after he was set free a bolt of lightning struck a rock and a shattered fragment tore his head off.
The Bodhisatta had seen these events and magically materialized seated cross-legged in mid-air to preach about the consequences of killing to the crowd that had gathered. He filled them with the fear of hell and all who heard him speak lived righteous lives from that point on.
In the Lifetime of the Buddha
When local people began killing goats, sheep, and other animals to offer to their departed relatives during a Feast of the Dead, some of the Buddha’s disciples asked him if any good could result from this. The Buddha answered that good never came from killing, even when the intention was noble, and told them this story as an example.
The Buddha did not identify any earlier births other than his own.