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كتاب التوحيد
97  
Oneness, Uniqueness of Allah (Tawheed)
(9)
Chapter: “And Allah is Ever All-Hearer, All-Seer.”
(9)
باب قَوْلِ اللَّهِ تَعَالَى ‏{‏وَكَانَ اللَّهُ سَمِيعًا بَصِيرًا‏}
Sahih al-Bukhari 7386

Narrated Abu Musa:

We were with the Prophet (ﷺ) on a journey, and whenever we ascended a high place, we used to say, "Allahu Akbar." The Prophet (ﷺ) said, "Don't trouble yourselves too much! You are not calling a deaf or an absent person, but you are calling One Who Hears, Sees, and is very near." Then he came to me while I was saying in my heart, "La hawla wala quwwatta illa billah (There is neither might nor power but with Allah)." He said, to me, "O `Abdullah bin Qais! Say, 'La hawla wala quwwata illa billah (There is neither might nor power but with Allah), for it is one of the treasures of Paradise." Or said, "Shall I tell you of it?"

حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا حَمَّادُ بْنُ زَيْدٍ، عَنْ أَيُّوبَ، عَنْ أَبِي عُثْمَانَ، عَنْ أَبِي مُوسَى، قَالَ كُنَّا مَعَ النَّبِيِّ صلى الله عليه وسلم فِي سَفَرٍ فَكُنَّا إِذَا عَلَوْنَا كَبَّرْنَا فَقَالَ ‏"‏ ارْبَعُوا عَلَى أَنْفُسِكُمْ، فَإِنَّكُمْ لاَ تَدْعُونَ أَصَمَّ وَلاَ غَائِبًا، تَدْعُونَ سَمِيعًا بَصِيرًا قَرِيبًا ‏"‏‏.‏ ثُمَّ أَتَى عَلَىَّ وَأَنَا أَقُولُ فِي نَفْسِي لاَ حَوْلَ وَلاَ قُوَّةَ إِلاَّ بِاللَّهِ‏.‏ فَقَالَ لِي ‏"‏ يَا عَبْدَ اللَّهِ بْنَ قَيْسٍ قُلْ لاَ حَوْلَ وَلاَ قُوَّةَ إِلاَّ بِاللَّهِ‏.‏ فَإِنَّهَا كَنْزٌ مِنْ كُنُوزِ الْجَنَّةِ ‏"‏‏.‏ أَوْ قَالَ أَلاَ أَدُلُّكَ بِهِ‏.‏
Reference : Sahih al-Bukhari 7386
In-book reference : Book 97, Hadith 16
USC-MSA web (English) reference : Vol. 9, Book 93, Hadith 484
  (deprecated numbering scheme)