Sunan Ibn Majah 959
سنن ابن ماجه#959Hasanحَدَّثَنَا مُحَمَّدُ بْنُ إِسْمَاعِيلَ، حَدَّثَنَا زَيْدُ بْنُ الْحُبَابِ، حَدَّثَنِي أَبُو الْمِقْدَامِ، عَنْ مُحَمَّدِ بْنِ كَعْبٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ نَهَى رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ أَنْ يُصَلَّى خَلْفَ الْمُتَحَدِّثِ وَالنَّائِمِ .
It was narrated that Ibn ‘Abbas said:“The Messenger of Allah (ﷺ) forbade performing prayer behind one who is engaged in conversation or one who is sleeping.”
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:
Al-AlbaniHasan
Muhammad Fouad Abd al-BaqiHasan
Zubair Ali ZaiHasan
In-book reference: 5:157