Musnad Ahmad 26:63

Abu Mu'awiyah narrated to us, Al-A'mash narrated to us, from Shaqiq, from Abdullah, who said: We were walking with the Prophet, peace and blessings of Allah be upon him, and he passed by Ibn Sayyad. He said: "I have hidden something for you." Ibn Sayyad said: "Dukh (smoke)." The Messenger of Allah, peace and blessings of Allah be upon him, said: "Be driven away, for you will never exceed your limit." Umar said: "O Messenger of Allah, let me strike his neck." He said: "No, if it is he whom you fear, you will not be able to kill him."