"The pot calling the kettle black" is a proverbial idiom that may be of Spanish origin, of which English versions began to appear in the first half of the 17th century.
"[3] The Spanish text at this point reads: Dijo el sartén a la caldera, Quítate allá ojinegra (Said the pan to the pot, get out of there black-eyes).
Among several variations, the one where the pan addresses the pot as culinegra (black-arse) makes clear that they are dirtied in common by contact with the cooking fire.
[5] This translation was also recorded in England soon afterwards as "The pot calls the pan burnt-arse" in John Clarke's collection of proverbs, Paroemiologia Anglo-Latina (1639).
For a Covetous Man to inveigh against Prodigality, an Atheist against Idolatry, a Tyrant against Rebellion, or a Lyer against Forgery, and a Drunkard against Intemperance, is for the Pot to call the Kettle black.