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كتاب المغازى
64  
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
(17)
Chapter: The Ghazwa of Uhud
(17)
باب غَزْوَةِ أُحُدٍ
Sahih al-Bukhari 4049

Narrated Zaid bin Thabit:

When we wrote the Holy Qur'an, I missed one of the Verses of Surat-al-Ahzab which I used to hear Allah's Messenger (ﷺ) reciting. Then we searched for it and found it with Khuza`ima bin Thabit Al-Ansari. The Verse was:-- 'Among the Believers are men Who have been true to Their Covenant with Allah, Of them, some have fulfilled Their obligations to Allah (i.e. they have been Killed in Allah's Cause), And some of them are (still) waiting" (33.23) So we wrote this in its place in the Qur'an.

حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ، حَدَّثَنَا ابْنُ شِهَابٍ، أَخْبَرَنِي خَارِجَةُ بْنُ زَيْدِ بْنِ ثَابِتٍ، أَنَّهُ سَمِعَ زَيْدَ بْنَ ثَابِتٍ ـ رضى الله عنه ـ يَقُولُ فَقَدْتُ آيَةً مِنَ الأَحْزَابِ حِينَ نَسَخْنَا الْمُصْحَفَ، كُنْتُ أَسْمَعُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقْرَأُ بِهَا، فَالْتَمَسْنَاهَا فَوَجَدْنَاهَا مَعَ خُزَيْمَةَ بْنِ ثَابِتٍ الأَنْصَارِيِّ ‏{‏مِنَ الْمُؤْمِنِينَ رِجَالٌ صَدَقُوا مَا عَاهَدُوا اللَّهَ عَلَيْهِ فَمِنْهُمْ مَنْ قَضَى نَحْبَهُ وَمِنْهُمْ مَنْ يَنْتَظِرُ ‏}‏ فَأَلْحَقْنَاهَا فِي سُورَتِهَا فِي الْمُصْحَفِ‏.‏
Reference : Sahih al-Bukhari 4049
In-book reference : Book 64, Hadith 95
USC-MSA web (English) reference : Vol. 5, Book 59, Hadith 379
  (deprecated numbering scheme)