Ahmad ibn Khalid reported: Muhammad ibn Ismaʿil narrated to us, from ʿAmr ibn Shuʿayb, from his father, from his grandfather, who said:

Al-Walid ibn al-Walid used to be frightened in his sleep, and he mentioned that to the Messenger of Allah, peace and blessings be upon him. The Prophet said to him, “When you lie down to sleep, say: ‘In the name of Allah. I seek refuge in the perfect words of Allah from His wrath and His punishment, from the evil of His servants, from the whisperings of the devils, and from their coming near me.’” He said those words, and the fear left him.

ʿAbd Allah ibn ʿAmr—may Allah be pleased with him—would teach these words to any of his children who were old enough to understand them; as for those who were still too young to grasp them, he would write them down and hang them around their necks.