Sahih Bukhari Volume 008, Book 073, Hadith Number 238.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 73. Good Manners and Form (Al-Adab)
Narated By Safiya bint Huyai : The wife of the Prophet that she went to Allah's Apostle while he was in Itikaf (staying in the mosque) during the last ten nights of the month of Ramadan. She spoke to him for an hour (a while) at night and then she got up to return home. The Prophet got up to accompany her, and when they reached the gate of the mosque opposite the dwelling place of Um Salama, the wife of the Prophet, two Ansari men passed by, and greeting Allah's Apostle , they quickly went ahead. Allah's Apostle said to them, "Do not be in a hurry She is Safiya, the daughter of Huyai." They said, "Subhan Allah! O Allah's Apostle (how dare we suspect you)." That was a great thing for both of them. The Prophet then said, "Satan runs in the body of Adam's son (i.e. man) as his blood circulates in it, and I was afraid that he (Satan) might insert an evil thought in your hearts."