The Bodhisatta was once a vulture and he took care of his elderly and infirm parents. One day while seeking flesh in a cemetery for them to eat, the Bodhisatta got his foot caught in a hunter’s snare. His first thought was not of himself, but that his parents would die because they had nobody else to care for them, and he lamented out loud about this. The hunter was shocked that a vulture could speak and impressed by the Bodhisatta’s dedication to his parents, so he set him free.
In the Lifetime of the Buddha
One time while discussing one of his disciples who supported his mother, the Buddha told this story as an example of how supporting parents is a good thing.
The hunter was an earlier birth of Channa, Prince Siddhartha’s charioteer who later became a disciple, and the Bodhisatta’s parents were earlier births of the king’s parents.