Jami` at-Tirmidhi 2843
جامع الترمذي#2843Sahihحَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ الْقَطَّانُ، حَدَّثَنَا فِطْرُ بْنُ خَلِيفَةَ، حَدَّثَنِي مُنْذِرٌ، وَهُوَ الثَّوْرِيُّ عَنْ مُحَمَّدِ ابْنِ الْحَنَفِيَّةِ، عَنْ عَلِيِّ بْنِ أَبِي طَالِبٍ، أَنَّهُ قَالَ يَا رَسُولَ اللَّهِ أَرَأَيْتَ إِنْ وُلِدَ لِي بَعْدَكَ أُسَمِّيهِ مُحَمَّدًا وَأُكْنِيهِ بِكُنْيَتِكَ قَالَ " نَعَمْ " . قَالَ فَكَانَتْ رُخْصَةً لِي . هَذَا حَدِيثٌ صَحِيحٌ .
Narrated 'Ali bin Abi Talib:that he said: "O Messenger of Allah (ﷺ)! If I have a son after you do you think I could name him your Kunyah?" He said: "Yes." So he said: "So that was permitted for me
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 43:117