I heard the Messenger of Allah (May Peace be upon him) say: When any of you wakes up from sleep, he should not put his hand in the utensil until he washes it three times, for none of you knows where his hand remained during the night or where it went round.
سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ إِذَا اسْتَيْقَظَ أَحَدُكُمْ مِنْ نَوْمِهِ فَلاَ يُدْخِلْ يَدَهُ فِي الإِنَاءِ حَتَّى يَغْسِلَهَا ثَلاَثَ مَرَّاتٍ فَإِنَّ أَحَدَكُمْ لاَ يَدْرِي أَيْنَ بَاتَتْ يَدُهُ أَوْ أَيْنَ كَانَتْ تَطُوفُ يَدُهُ