عَنْ حَمَّادِ بْنِ سَلَمَةَ عَنْ حُمَيْدٍ وَأَيُّوبَ عَنْ عِكْرِمَةَ عَنِ ابْنِ عَبَّاسٍ رَضِيَ اللَّهُ عَنْهُ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ نَامَ حَتَّى سُمِعَ لَهُ غَطِيطٌ فَقَامَ فَصَلَّى وَلَمْ يَتَوَضَّأْ، فَقَالَ عِكْرِمَةُ: كَانَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ مَحْفُوظًا
It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Whoever falls asleep in the state of prostration, there is no ablution upon him; ablution is required for the one who sleeps lying down, because when a servant sleeps lying down, his joints become loose and relaxed.