The Bodhisatta was once a woodpecker, and coming across a lion with a bone stuck in his throat he removed the bone, after having fixed a stick in the lion's mouth to prevent him from biting off the head of his rescuer.
Later, he saw the lion eating the carcase of a buffalo and asked for a boon. The lion refused, saying it was enough for him to have escaped death after putting his head into a lion's jaws.
The lion is identified with Devadatta, and the story was related in reference to his ingratitude. J.iii.25-7; cp. Jātakamāla No.xxxiv.