Sunan an-Nasa'i 161
سنن النسائي#161Sahihأَخْبَرَنَا إِسْمَاعِيلُ بْنُ مَسْعُودٍ، وَحُمَيْدُ بْنُ مَسْعَدَةَ، قَالاَ حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، قَالَ حَدَّثَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ أَبِي سَلَمَةَ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا اسْتَيْقَظَ أَحَدُكُمْ مِنْ مَنَامِهِ فَلاَ يُدْخِلْ يَدَهُ فِي الإِنَاءِ حَتَّى يُفْرِغَ عَلَيْهَا ثَلاَثَ مَرَّاتٍ فَإِنَّهُ لاَ يَدْرِي أَيْنَ بَاتَتْ يَدُهُ " .
It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said:"When any one of you wakes from sleep, let him not put his hand into the vessel until he has washed it three times, because he does not know where his hand spent the night
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: 1:162