Arabic (Original)
أَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ نا أَبُو الْحَسَنِ مُحَمَّدُ بْنُ مُوسَى الصَّيْدَلَانِيُّ نا إِبْرَاهِيمُ بْنُ أَبِي طَالِبٍ ثنا مُحَمَّدُ بْنُ الْمُثَنَّى ثنا عَبْدُ الرَّحْمَنِ بْنُ مَهْدِيٍّ عَنْ سُفْيَانَ عَنِ الْأَعْمَشِ وَمَنْصُورٍ عَنْ إِبْرَاهِيمَ عَنْ عَبْدِ الرَّحْمَنِ بْنِ يَزِيدَ عَنْ سَلْمَانَ قَالَ قَالَ لَهُ الْمُشْرِكُونَ إِنَّا نَرَى صَاحِبَكُمْ يُعَلِّمُكُمْ حَتَّى يُعَلِّمَكُمُ الْخِرَاءَةَ؟ قَالَ أَجَلْ إِنَّهُ نَهَانَا أَنْ يَسْتَنْجِيَ أَحَدُنَا بِيَمِينِهِ وَأَنْ يَسْتَقْبِلَ الْقِبْلَةَ وَنَهَانَا عَنِ الرَّوْثِ وَالْعِظَامِ وَقَالَ لَا يَسْتَنْجِ أَحَدُكُمْ بِدُونِ ثَلَاثَةِ أَحْجَارٍ
English Translation
Abdullah ibn Abbas narrated that the Prophet (peace be upon him) prostrated and slept during his prostration until he was heard breathing heavily (or snoring). Then he got up and prayed. It was said: "O Messenger of Allah, you fell asleep during your prayer?" He said: "Wudu is only required for the one who sleeps while lying down, for when he lies down, his joints relax."