An Ass, put on the Lion's skin, went around the forest and amused himself by scaring the foolish animals he met in his travels.
And than he came upon a Fox, he tried to scare him too, but the Fox no sooner heard the sound of his voice than he exclaimed, "I might possibly have been frightened myself, if I had not heard your bray."
Moral: Clothes may disguise a fool, but his words will give him away
- - AESOP