The Farmer and the Viper

The Farmer and the Viper is one of Aesop's Fables, numbered 176 in the Perry Index. It has the moral that kindness to the evil will be met by betrayal and is the source of the idiom 'to nourish a viper in one's bosom'. The fable is not to be confused with The Snake and the Farmer, which looks back to a situation when friendship was possible between the two.

The story concerns a farmer who finds a viper freezing in the snow. Taking pity on it, he picks it up and places it within his coat. The viper, revived by the warmth, bites his rescuer, who dies realizing that it is his own fault. The story is recorded in both Greek and Latin sources. In the former, the farmer dies reproaching himself "for pitying a scoundrel," while in the version by Phaedrus the snake says that he bit his benefactor "to teach the lesson not to expect a reward from the wicked." The latter sentiment is made the moral in Medieval versions of the fable. Odo of Cheriton's snake answers the farmer's demand for an explanation with a counter-question, "Did you not know that there is enmity and natural antipathy between your kind and mine? Did you not know that a serpent in the bosom, a mouse in a bag and fire in a barn give their hosts an ill reward?"

Aesop's fable was so widespread in Classical times that allusions to it became proverbial. One of the very earliest is in a poem by the 6th century BCE Greek poet Theognis of Megara, who refers to a friend who has betrayed him as the 'chill and wily snake that I cherished in my bosom'. In the work of Cicero it appears as In sinu viperam habere (to have a snake in the breast) and in Erasmus' 16th century collection of proverbial phrases, the Adagia, as Colubrum in sinu fovere (to nourish a serpent in one's bosom). The usual English form is 'to nourish a snake (or viper) in one's bosom', a phrase used by Geoffrey Chaucer (Merchant's Tale, line 1786), William Shakespeare (Richard II 3.2.129–31,) John Milton (Samson Agonistes, line 763) and John Dryden (All for Love 4.1.464–66), among the foremost.

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