"The Messenger of Allah would fall asleep until he was breathing deeply, then he would get up and offer the prayer, and he did not perform ablution." (Hasan) Tanafisi said: "Wakiʿ said: 'She meant while he was prostrating (he would sleep).'"  

كَانَ رَسُولُ اللَّهِ ﷺ يَنَامُ حَتَّى يَنْفُخَ ثُمَّ يَقُومُ فَيُصَلِّي وَلاَ يَتَوَضَّأُ قَالَ الطَّنَافِسِيُّ قَالَ وَكِيعٌ تَعْنِي وَهُوَ سَاجِدٌ  

The Messenger of Allah slept until he was breathing deeply, then he got up and prayed.  

أَنَّ رَسُولَ اللَّهِ ﷺ نَامَ حَتَّى نَفَخَ ثُمَّ قَامَ فَصَلَّى  

"He would sleep like that while he was sitting up."  

كَانَ نَوْمُهُ ذَلِكَ وَهُوَ جَالِسٌ يَعْنِي النَّبِيَّ ﷺ  

The Messenger of Allah said: "The eye is the leather strap (that ties up) the anus, so whoever falls asleep, let him perform ablution."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ الْعَيْنُ وِكَاءُ السَّهِ فَمَنْ نَامَ فَلْيَتَوَضَّأْ  

"The Messenger of Allah used to command us not to take off our leather socks for three days except in the case of sexual impurity, but not in the case of defecation, urine or sleep (i.e. during travel)."  

كَانَ رَسُولُ اللَّهِ ﷺ يَأْمُرُنَا أَنْ لاَ نَنْزِعَ خِفَافَنَا ثَلاَثَةَ أَيَّامٍ إِلاَّ مِنْ جَنَابَةٍ لَكِنْ مِنْ غَائِطٍ وَبَوْلٍ وَنَوْمٍ