a wolf in sheep's clothing批著羊皮的狼；貌善心惡的人
耶穌在加利利一帶傳道布教，收了很多信徒 。有一天，他對門徒說:"Beware of false prophets,which come to you in sheep's clothing,but inwardly they are ravening wolves""
eg:Mrs.Martin trusted the lawyer until she realized that he was a wolf in sheep's clothing