Ibn Babawayh has through reliable chains narrated from Imam Ja’far Sadiq (a.s.) that a Bedouin came to the Holy Prophet (S) and said in a ridiculing manner: “Are you not the best and most exalted among us from the days of Ignorance and Islam? This angered the Prophet and he said: “O Bedouin, how many veils are there on your tongue.”
“Two veils,” He replied, “Lips and teeth.” The Holy Prophet (S) said: “Is none of them able to restrain the harshness of your tongue from us?” Then he said: “From all that which is given to man in the world, nothing harms him more than the excessive use of the tongue. O Ali, cut off his tongue.” People thought that it will be done literally, by Amirul Momineen (a.s.) gave him a few dirhams and sent him away.