Sahih al-Bukhari 2594
صحيح البخاري#2594Sahihوَقَالَ بَكْرٌ عَنْ عَمْرٍو، عَنْ بُكَيْرٍ، عَنْ كُرَيْبٍ، مَوْلَى ابْنِ عَبَّاسٍ إِنَّ مَيْمُونَةَ زَوْجَ النَّبِيِّ صلى الله عليه وسلم أَعْتَقَتْ وَلِيدَةً لَهَا فَقَالَ لَهَا " وَلَوْ وَصَلْتِ بَعْضَ أَخْوَالِكِ كَانَ أَعْظَمَ لأَجْرِكِ ".
Narrated Maimuna, the wife of the Prophet (ﷺ) that she manumitted her slave-girl and the Prophet (ﷺ) said to her, "You would have got more reward if you had given the slave-girl to one of your maternal uncles
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:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 51:28