E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
To eat together in the East was at one time a sure pledge of protection. A Persian nobleman was once sitting in his garden, when a man prostrated himself before him, and implored protection from the rabble. The nobleman gave him the remainder of a peach which he was eating, and when the incensed multitude arrived, and declared that the man had slain the only son of the nobleman, the heart-broken father replied, We have eaten together; go in peace, and would not allow the murderer to be punished.