Sunan an-Nasa'i 120
It was narrated that Usamah bin Zaid said:
"The Messenger of Allah ﷺ and Bilal entered Al-Aswaf [1] and he went to relieve himself and then came out." Usamah said: "I asked Bilal: 'What did he do?' Bilal said: 'The Prophet ﷺ went to relieve himself, then he performed Wudu', so he washed his hands and face, and wiped his head and he wiped over his Khuffs, then prayed.'"
أَخْبَرَنَا عَبْدُ الرَّحْمَنِ بْنُ إِبْرَاهِيمَ، دُحَيْمٌ وَسُلَيْمَانُ بْنُ دَاوُدَ - وَاللَّفْظُ لَهُ - عَنِ ابْنِ نَافِعٍ، عَنْ دَاوُدَ بْنِ قَيْسٍ، عَنْ زَيْدِ بْنِ أَسْلَمَ، عَنْ عَطَاءِ بْنِ يَسَارٍ، عَنْ أُسَامَةَ بْنِ زَيْدٍ، قَالَ دَخَلَ رَسُولُ اللَّهِ ﷺ وَبِلاَلٌ الأَسْوَاقَ فَذَهَبَ لِحَاجَتِهِ ثُمَّ خَرَجَ قَالَ أُسَامَةُ فَسَأَلْتُ بِلاَلاً مَا صَنَعَ فَقَالَ بِلاَلٌ ذَهَبَ النَّبِيُّ ﷺ لِحَاجَتِهِ ثُمَّ تَوَضَّأَ فَغَسَلَ وَجْهَهُ وَيَدَيْهِ وَمَسَحَ بِرَأْسِهِ وَمَسَحَ عَلَى الْخُفَّيْنِ ثُمَّ صَلَّى .