Farwah bin Nawfal Ashja'i narrates from his father that he said: I presented myself before the Prophet Muhammad (peace be upon him) and said: O Messenger of Allah! Teach me something that I may recite when I go to bed. The Prophet (peace be upon him) said: Recite this «قُلْ يَا أَيُّهَا الْكَافِرُونَ».