Speaking of The Snake and the Crab in Ancient Greece was the equivalent of the modern idiom, 'Pot calling the kettle black'. A fable attributed to Aesop was eventually created about the two creatures and later still yet another fable concerning a crab and its offspring was developed to make the same point.
The crab spoke thus,
- seizing the snake in its claws,
- 'One’s comrade should be straight
- and not think crooked thoughts.’