Sahih Muslim
The Book of Mosques and Places of Prayer — Hadith #1216
Scholarly Consensus: Sahih How we grade
حَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا سُفْيَانُ بْنُ عُيَيْنَةَ، عَنْ عَمْرٍو، قَالَ أَخْبَرَنِي بِذَا أَبُو مَعْبَدٍ، - ثُمَّ أَنْكَرَهُ بَعْدُ - عَنِ ابْنِ عَبَّاسٍ، قَالَ كُنَّا نَعْرِفُ انْقِضَاءَ صَلاَةِ رَسُولِ اللَّهِ صلى الله عليه وسلم بِالتَّكْبِيرِ .
We used to know that Allah’s Messenger (ﷺ) had finished his prayer when we heard the takbir (Allah-O-Akbar).
Chain of Narration (Isnad)
Hadith Grading
Each grade below reflects one scholar's assessment of the chain of transmission. The grade describes the chain, not the Prophet's words. How we grade
Scholarly Consensus: Sahih