"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." (Using translation from Nasāʾī 161)
أَخْبَرَهُ أَنَّ النَّبِيَّ ﷺ قَالَ إِذَا اسْتَيْقَظَ أَحَدُكُمْ مِنْ مَنَامِهِ فَلْيُفْرِغْ عَلَى يَدَيْهِ ثَلَاثَ مَرَّاتٍ قَبْلَ أَنْ يُدْخِلَهُمَا فِي الْإِنَاءِ فَإِنَّهُ لَا يَدْرِي فِيمَ بَاتَتْ يَدُهُ