‘Uqbah Ibn ‘Amir reported:

"I followed the Messenger of Allah (ﷺ) when he was riding, and I placed my hand on his foot and said : O Messenger of Allah, teach me Sūrah Hud and Sūrah Yusuf. He said: 'You will never recite anything greater (for refuge) before Allah than: "Qul a’oodhu birabbil falaq (Surat al-Falaq)”, and “Qul a’oodhu birabbin-naas (Surat al-Nās).” Reference: Sunan an-Nasa'i 953, also collected in Sunan Al-Dārimī, no. 3343.

عَنْ عُقْبَةَ بْنِ عَامِرٍ، قَالَ اتَّبَعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم وَهُوَ رَاكِبٌ فَوَضَعْتُ يَدِي عَلَى قَدَمِهِ فَقُلْتُ أَقْرِئْنِي يَا رَسُولَ اللَّهِ سُورَةَ هُودٍ وَسُورَةَ يُوسُفَ ‏.‏ فَقَالَ ‏

‏ لَنْ تَقْرَأَ شَيْئًا أَبْلَغَ عِنْدَ اللَّهِ مِنْ (‏ قُلْ أَعُوذُ بِرَبِّ الْفَلَقِ ‏)‏ وَ (‏ قُلْ أَعُوذُ بِرَبِّ النَّاسِ ‏)‏ ‏

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