Sahih al-Bukhari 4641
Sahih al-Bukhari · Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)) · Allah's Saying: "And say ... Hittatun..." [i.e., (O Allah) forgive our sins] (V.7:161)
Narrated Abu Huraira:
حَدَّثَنَا إِسْحَاقُ ، أَخْبَرَنَا عَبْدُ الرَّزَّاقِ ، أَخْبَرَنَا مَعْمَرٌ ، عَنْ هَمَّامِ بْنِ مُنَبِّهٍ ، أَنَّهُ سَمِعَ أَبَا هُرَيْرَةَ ـ رضى الله عنه ـ يَقُولُ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " قِيلَ لِبَنِي إِسْرَائِيلَ {ادْخُلُوا الْبَابَ سُجَّدًا وَقُولُوا حِطَّةٌ نَغْفِرْ لَكُمْ خَطَايَاكُمْ} فَبَدَّلُوا فَدَخَلُوا يَزْحَفُونَ عَلَى أَسْتَاهِهِمْ وَقَالُوا حَبَّةٌ فِي شَعَرَةٍ " .
Allah's Messenger (ﷺ) said, "It was said to the children of Israel, 'Enter the gate in prostration and say Hitatun. (7.161) We shall forgive you, your faults.' But they changed (Allah's Order) and entered, dragging themselves on their buttocks and said, 'Habatun (a grain) in a Sha'ratin (hair).