The Bodhisatta was once an ascetic who had many followers. A jackal came each night and fouled their well. One night some of the ascetics surrounded the jackal and caught it. They brought it before the Bodhisatta who asked why it was doing this. The jackal answered that it was the nature of jackals to spoil the spots where they drink (his father and grandfather had done the same), so nobody should be angry with him. The Bodhisatta condemned all jackals as foul beasts and told this one to go away and never return.
In the Lifetime of the Buddha
The jackal of the past was an earlier birth of a jackal who used to foul a well at the Buddha’s monastery. One time when some novices saw it, they pelted it with clods of dirt and it never returned. When the Buddha heard some disciples discussing the incident, he told them this story so they knew that the same jackal had also fouled his well in the past.