Sunan Ibn Majah 960
سنن ابن ماجه#960Sahihحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا مُحَمَّدُ بْنُ عُبَيْدٍ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ كَانَ النَّبِيُّ ـ صلى الله عليه وسلم ـ يُعَلِّمُنَا أَنْ لاَ نُبَادِرَ الإِمَامَ بِالرُّكُوعِ وَالسُّجُودِ وَإِذَا كَبَّرَ فَكَبِّرُوا وَإِذَا سَجَدَ فَاسْجُدُوا .
It was narrated that Abu Hurairah said:“The Prophet (ﷺ) used to teach us not to bow or prostrate before the Imam; when he says the Takbir then say the Takbir, and when he prostrates, you should prostrate.”
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: 5:158