Sunan an-Nasa'i 616
سنن النسائي#616Sahihأَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ، قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ، - وَهُوَ ابْنُ الْمُبَارَكِ - عَنْ سُلَيْمَانَ بْنِ الْمُغِيرَةِ، عَنْ ثَابِتٍ، عَنْ عَبْدِ اللَّهِ بْنِ رَبَاحٍ، عَنْ أَبِي قَتَادَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لَيْسَ فِي النَّوْمِ تَفْرِيطٌ إِنَّمَا التَّفْرِيطُ فِيمَنْ لَمْ يُصَلِّ الصَّلاَةَ حَتَّى يَجِيءَ وَقْتُ الصَّلاَةِ الأُخْرَى حِينَ يَنْتَبِهُ لَهَا " .
It was narrated that Abu Qatadah said:"The Messenger of Allah (ﷺ) said: 'There is no negligence when one sleeps, rather negligence is when one does not offer one prayer until the time of the next prayer comes and he realizes that he has missed a prayer
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: 6:123