The Prophet ﷺ entrusted the daughter of Umm Salama to me and said, "You are simply her nurse."He stayed for as long as Allah willed, then he came to the Prophet, who asked, "What has the girl, or the little girl, been doing?"He replied, "She is with her mother."The Prophet asked, "Then what has brought you here?"He said, "So that you may teach me what to say when I go to sleep."The Prophet said, "When you go to sleep, recite 'Say, disbelievers' [Kafirun 109:1]. Then sleep upon its ending, for it is a declaration of freedom from shirk."
دفع إلي النبي ﷺ ابنة أم سلمة، وقال: إنما أنت ظئري قال: فمكث ما شاء الله، ثم أتيته، فقال: ما فعلت الجارية، أو الجويرية؟ قال: قلت: عند أمها، قال: فمجيء ما جئت؟ قال: قلت: تعلمني ما أقول عند منامي، فقال: اقرأ عند منامك {قل يأيها الكفرون} قال: ثم نم على خاتمتها، فإنها براءة من الشرك.
Ahmad (23807), Tirmidhi (2403), and Hakim (1/565) all narrated it through multiple chains from Israil, from Abu Ishaq, from Farwa bin Nawfal Ashjai, from his father, and he mentioned it. The wording is that of Ahmad and Hakim, while Tirmidhi referred back to the hadith before it, saying, "with the same meaning." Abu Dawud (5055) also narrated it, and Ibn Hibban (790) and Hakim (2/538) graded it sahih, through multiple chains from Zuhayr bin Muawiya, from Abu Ishaq, with similar wording.Its chain is hasan because of Farwa bin Nawfal, for he is hasan al-hadith. It has been said that he was a companion, but the correct view is that he was a taabii. There has been considerable disagreement regarding the chain going back to Abu Ishaq Sabi, but the sahih view is the narration of Israil and those who followed him, as Tirmidhi and Daraqutni stated in Ilal (13/277). Hakim said, "This is a hadith sahih in its chain," and Ibn Hajar graded it hasan in Nataij Afkar (3/61-62).This hadith has also been narrated through a different route. Ibn Abu Shayba (27060) narrated it through Abu Malik Ashjai (who is Saad bin Tariq), from Abdul-Rahman bin Nawfal Ashjai, from his father, and he mentioned it. Abdul-Rahman bin Nawfal was declared trustworthy by Ajli, and Ibn Hibban mentioned him among the trustworthy narrators. This constitutes a corroboration of the preceding narration.