The Bodhisatta was once an ascetic with many followers. There were many snakes around their home and many of his fellow ascetics died from snake bites. The Bodhisatta called an assembly and told the others that if they showed kindness to the four royal races of snakes, no snakes would do them any harm. Then he reminded them they should love all creatures on Earth; two feet, four feet, more, or none. The other ascetics followed the Bodhisatta’s advice and all snakes around their home departed.
In the Lifetime of the Buddha
While one of the Buddha’s disciples sat in his quarters chopping sticks, a snake crawled out of a rotten log and bit him on the toe. He died instantly. The Buddha told other disciples that if this unfortunate disciple had shown kindness to the four royal races of snakes he would not have been bit, and he then told this story to illustrate the point.
The Bodhisatta’s followers were earlier birth of the Buddha’s followers.