Hazrat Naufal narrates that the Messenger of Allah, peace and blessings be upon him, said to him: "What has brought you here?" I submitted: "O Messenger of Allah, peace and blessings be upon you! I have come so that you may teach me a supplication to recite at bedtime." The Prophet, peace and blessings be upon him, said: "When you lie down on your bed, recite Surah Al-Kafirun, and after completing it, go to sleep. For this Surah is a declaration of freedom from shirk (associating partners with Allah)."