Language:
كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
Sahih al-Bukhari 4479

Narrated Abu Huraira:

The Prophet (ﷺ) said, "It was said to the children of Israel, 'Enter the gate (of the town), prostrate (in humility) and say: Hittatun (i.e. repentance) i.e. O Allah! Forgive our sins.' But they entered by dragging themselves on their buttocks, so they did something different (from what they had been ordered to do) and said, 'Hittatun,' but added, "A grain in a hair."

حَدَّثَنِي مُحَمَّدٌ، حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ مَهْدِيٍّ، عَنِ ابْنِ الْمُبَارَكِ، عَنْ مَعْمَرٍ، عَنْ هَمَّامِ بْنِ مُنَبِّهٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏"‏ قِيلَ لِبَنِي إِسْرَائِيلَ ‏{‏ادْخُلُوا الْبَابَ سُجَّدًا وَقُولُوا حِطَّةٌ‏}‏ فَدَخَلُوا يَزْحَفُونَ عَلَى أَسْتَاهِهِمْ، فَبَدَّلُوا وَقَالُوا حِطَّةٌ، حَبَّةٌ فِي شَعَرَةٍ ‏"‏‏.‏
Reference : Sahih al-Bukhari 4479
In-book reference : Book 65, Hadith 6
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 6
  (deprecated numbering scheme)