Sahih al-Bukhari 6505

Ibn Shihab related from 'Ali ibn Husyan that Safiyya bint Huyayy came to the Prophet, may Allah bless him and grant him peace, [when he was doing i'tikaf in the mosque] and when she returned (home), he accompanied her. Two men of the Ansar passed by him and he called out to them, saying, 'It is Safiyya.' The two said, Glory be to Allah!' He said, 'Shaytan flows through the son of Adam like blood does.'" Az-Zuhri related it from 'Ali ibn Husayn from 'Ali from the Prophet, may Allah bless him and grant him peace. XXII. Chapter. A ruler commanding two amirs whom he sends to the same place to obey one another and not disobey one another