Sahih al-Bukhari 1226
صحيح البخاري#1226Sahihحَدَّثَنَا أَبُو الْوَلِيدِ، حَدَّثَنَا شُعْبَةُ، عَنِ الْحَكَمِ، عَنْ إِبْرَاهِيمَ، عَنْ عَلْقَمَةَ، عَنْ عَبْدِ اللَّهِ ـ رضى الله عنه ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم صَلَّى الظُّهْرَ خَمْسًا فَقِيلَ لَهُ أَزِيدَ فِي الصَّلاَةِ فَقَالَ " وَمَا ذَاكَ ". قَالَ صَلَّيْتَ خَمْسًا. فَسَجَدَ سَجْدَتَيْنِ بَعْدَ مَا سَلَّمَ.
Narrated' `Abdullah:Once Allah's Messenger (ﷺ) offered five rak`at in the Zuhr prayer, and somebody asked him whether there was some increase in the prayer. Allah's Messenger (ﷺ) said, "What is that?" He said, "You have offered five rak`at." So Allah's Messenger (ﷺ) performed two prostrations of Sahu after Taslim
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: 22:3