The Bodhisatta was once a lizard. One day he saw that an ascetic had taken up residence nearby in a hut made of leaves. Assuming he was a holy man, the Bodhisatta visited regularly to pay respect. One time a supporter of the ascetic gave him some lizard meat to eat and he liked it so much he decided to kill and eat the Bodhisatta. The ascetic prepared the ingredients he would need for cooking (ghee, curds, condiments, and the like) and sat at the door of his hut with a mallet hidden under his robe waiting for the Bodhisatta to come.
When the Bodhisatta arrived he noticed that something about the ascetic was not right and guessed what his plan was. He walked downwind and the ascetic’s scent confirmed his suspicions. So the Bodhisatta walked away without stopping, prompting the ascetic to throw his mallet, but it hit just the tip of his tail. The Bodhisatta told him, “you missed me, but you will not miss your punishments in hell,” and ran off to hide in an ant hill. He popped his head out a hole other than the one he had used to go in and hurled insults at the wicked ascetic, telling him that if he stayed he would expose him to all the people living around. And so the ascetic went away.
In the Lifetime of the Buddha
The false ascetic was an earlier birth of one of the Buddha’s disciples who had been exposed as a cheater. The Buddha told this story so the other disciples knew this disciple had also been a rogue in the past.