ENOfficial
Farwah b. Nawfal quoted his father as saying that the Prophet (ﷺ) said to Nawfal (his father): Recite (the Surah) 'Say, O you disbelievers!' and then go to sleep at its end, for it is a declaration of freedom from polytheism.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا النُّفَيْلِيُّ، حَدَّثَنَا زُهَيْرٌ، حَدَّثَنَا أَبُو إِسْحَاقَ، عَنْ فَرْوَةَ بْنِ نَوْفَلٍ، عَنْ أَبِيهِ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ لِنَوْفَلٍ " اقْرَأْ { قُلْ يَا أَيُّهَا الْكَافِرُونَ } ثُمَّ نَمْ عَلَى خَاتِمَتِهَا فَإِنَّهَا بَرَاءَةٌ مِنَ الشِّرْكِ " .
sunnah.com