农夫在冬天发现一条冻僵了的蛇，他可怜这条蛇，拿来放在自己的怀里。蛇温暖过来，恢复了他的本性，咬他的恩人，把农夫害死了。农夫将死的时候说到：“我是该死，怜惜恶人。”

这故事说明，邪恶的人们是不会变得，即使人家对他十分仁善。（周启明译）

伊索寓言之《农夫和蛇的故事》（英文版）
　　Aesop’s Fables
　　The Woodman and the Serpent
　　
　　One wintry day a Woodman was tramping home from his work when he saw something black lying on the snow. When he came closer he saw it was a Serpent to all appearance dead. But he took it up and put it in his bosom to warm while he hurried home. As soon as he got indoors he put the Serpent down on the hearth before the fire. The children watched it and saw it slowly come to life again. Then one of them stooped down to stroke it, but thc Serpent raised its head and put out its fangs and was about to sting the child to death. So the Woodman seized his axe, and with one stroke cut the Serpent in two. ‘Ah,’ said he,
　　
　　‘No gratitude from the wicked.’