Musnad Ahmad 1164:6

'Abd al-Razzaq narrated to us, he said: Ma'mar and 'Abd al-A'la informed us, from Ma'mar, from al-Zuhri, from 'Ali ibn al-Husayn, from Safiyyah bint Huyayy, she said: The Messenger of Allah (peace and blessings of Allah be upon him) was in I'tikaf. I came to him to visit him at night, and I spoke with him. Then I stood up to return, and he stood up with me to see me off—and her dwelling was in the house of Usamah ibn Zayd. Two men from the Ansar passed by, and when they saw the Prophet (peace and blessings of Allah be upon him), they quickened their pace. The Prophet (peace and blessings of Allah be upon him) said: "Slow down, it is Safiyyah bint Huyayy." They said: "Subhan Allah, O Messenger of Allah!" He said: "Indeed, the Shaytan flows through the human being like the flow of blood, and I feared that he might cast evil—or he said: 'something'—into your hearts."