Mishkat al-Masabih
Mishkat al-Masabih 466
وَعَنْ نَافِعٍ قَالَ: انْطَلَقْتُ مَعَ ابْنِ عُمَرَ فِي حَاجَة إِلَى ابْن عَبَّاس فَقَضَى ابْنُ عُمَرَ حَاجَتَهُ وَكَانَ مِنْ حَدِيثِهِ يَوْمَئِذٍ أَنْ قَالَ مَرَّ رَجُلٌ فِي سِكَّةٍ مِنَ السِّكَكِ فَلَقِيَ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَقَدْ خَرَجَ مِنْ غَائِطٍ أَوْ بَوْلٍ فَسَلَّمَ عَلَيْهِ فَلَمْ يَرُدَّ عَلَيْهِ حَتَّى كَادَ الرَّجُلُ أَنْ يَتَوَارَى فِي السِّكَّةِ ضَرَبَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بِيَدَيْهِ عَلَى الْحَائِطِ وَمَسَحَ بِهِمَا وَجْهَهُ ثُمَّ ضَرَبَ ضَرْبَةً أُخْرَى فَمَسَحَ ذِرَاعَيْهِ ثُمَّ رَدَّ عَلَى الرَّجُلِ السَّلَامَ وَقَالَ: «إِنَّهُ لَمْ يَمْنَعْنِي أَنْ أَرُدَّ عَلَيْكَ السَّلَامَ إِلَّا أَنِّي لَمْ أَكُنْ على طهر» . رَوَاهُ أَبُو دَاوُد
Nāfiʿ said: ‘I went with Ibn ʿUmar on an errand to Ibn ʿAbbās. After Ibn ʿUmar had taken care of his need, he related to me that a man walking along a street met the Messenger of Allah as he was coming from relieving himself—or urinating—and greeted him. The Messenger did not reply until the man was nearly out of sight. The Messenger then struck his hands against a wall and wiped his face with them, struck the wall again and wiped his forearms, then returned the man’s greeting. He said: “Nothing prevented me from returning your greeting except that I was not in a state of ritual purity.”’ Abū Dāwūd transmitted it.