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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(42)
"Guard strictly the (five obligatory) A.s-Salawãt (the prayers), especially the middle SaM! (i.e., the best prayer - 'Asr) .. ." (V.2:238)
(42)
Sahih al-Bukhari 4530

Narrated Ibn Az-Zubair:

I said to `Uthman bin `Affan (while he was collecting the Qur'an) regarding the Verse:-- "Those of you who die and leave wives ..." (2.240) "This Verse was abrogated by an other Verse. So why should you write it? (Or leave it in the Qur'an)?" `Uthman said. "O son of my brother! I will not shift anything of it from its place."

حَدَّثَنِي أُمَيَّةُ بْنُ بِسْطَامٍ، حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، عَنْ حَبِيبٍ، عَنِ ابْنِ أَبِي مُلَيْكَةَ، قَالَ ابْنُ الزُّبَيْرِ قُلْتُ لِعُثْمَانَ بْنِ عَفَّانَ ‏{‏وَالَّذِينَ يُتَوَفَّوْنَ مِنْكُمْ وَيَذَرُونَ أَزْوَاجًا‏}‏ قَالَ قَدْ نَسَخَتْهَا الآيَةُ الأُخْرَى فَلِمَ تَكْتُبُهَا أَوْ تَدَعُهَا قَالَ يَا ابْنَ أَخِي، لاَ أُغَيِّرُ شَيْئًا مِنْهُ مِنْ مَكَانِهِ‏.‏
Reference : Sahih al-Bukhari 4530
In-book reference : Book 65, Hadith 53
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 53
  (deprecated numbering scheme)