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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(3b)
The Statement of Allah the Most High: '... and believes in Al-Ḥusnā." (1)(V.92:6) (1): (Ch.) The best (i.e., either Lā ilāha illallāh: none has the right to be worshipped but Allah) or a reward from Allah (i.e., Allah will compensate him for what he will spend in Allah's way or bless him with Paradise).
(3 م)
بَابُ: {وَصَدَّقَ بِالْحُسْنَى}
Sahih al-Bukhari 4945b

Narrated Abu `Abdur-Rahman:

`Ali said, "We were sitting with the Prophet," (He then mentioned the Hadith above (469).

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا عَبْدُ الْوَاحِدِ، حَدَّثَنَا الأَعْمَشُ، عَنْ سَعْدِ بْنِ عُبَيْدَةَ، عَنْ أَبِي عَبْدِ الرَّحْمَنِ، عَنْ عَلِيٍّ ـ رضى الله عنه ـ قَالَ كُنَّا قُعُودًا عِنْدَ النَّبِيِّ صلى الله عليه وسلم فَذَكَرَ الْحَدِيثَ‏.‏
Reference : Sahih al-Bukhari 4945b
In-book reference : Book 65, Hadith 467
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 470
  (deprecated numbering scheme)