Abu Dawud
Jihad
Book Number: 008 / Hadith Number: 2646
Narated By Furat ibn Hayyan : The Apostle of Allah (pbuh) commanded to kill him: he was a spy of AbuSufyan and an ally of a man of the Ansar. He passed a circle of the Ansar and said: I am a Muslim. A man from the Ansar said, Apostle of Allah, he is saying that he is a Muslim. The Apostle of Allah (pbuh) said: There are people among you in whose faith we trust. Furat ibn Hayyan is one of them.