Chapter: Ablution after sleep. And whoever considers it unnecessary to repeat ablution after dozing once or twice or after nodding once in slumber
Narrated Anas:The Prophet (ﷺ) said, "If anyone of you feels drowsy while praying, he should sleep till he understands what he is saying (reciting).
Reference
Sahih al-Bukhari 213
In-book reference
Book 4, Hadith 79
USC-MSA web (English)
Vol. 1, Book 4, Hadith 212
Translation by Dr. M. Muhsin Khan · Language: EN
Sahih
Arabic Text
حَدَّثَنَا أَبُو مَعْمَرٍ، قَالَ حَدَّثَنَا عَبْدُ الْوَارِثِ، حَدَّثَنَا أَيُّوبُ، عَنْ أَبِي قِلاَبَةَ، عَنْ أَنَسٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِذَا نَعَسَ أَحَدُكُمْ فِي الصَّلاَةِ فَلْيَنَمْ حَتَّى يَعْلَمَ مَا يَقْرَأُ ".