Hadith 55

Sahih Bukhari

Book 4: Ablutions (Wudu')

Chapter 40

The using of the remaining water after ablution

باب اسْتِعْمَالِ فَضْلِ وَضُوءِ النَّاسِ

And Jarir bin ‘Abdullah ordered the members of his family to perform ablution with the water in which he had put his Siwak (a piece of a root of a tree called Al-Arak used as a toothbrush). ​​
وَأَمَرَ جَرِيرُ بْنُ عَبْدِ اللَّهِ أَهْلَهُ أَنْ يَتَوَضَّئُوا بِفَضْلِ سِوَاكِهِ.
Sahih al-Bukhari 189
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، قَالَ حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ بْنِ سَعْدٍ، قَالَ حَدَّثَنَا أَبِي، عَنْ صَالِحٍ، عَنِ ابْنِ شِهَابٍ، قَالَ أَخْبَرَنِي مَحْمُودُ بْنُ الرَّبِيعِ، قَالَ وَهُوَ الَّذِي مَجَّ رَسُولُ اللَّهِ صلى الله عليه وسلم فِي وَجْهِهِ وَهْوَ غُلاَمٌ مِنْ بِئْرِهِمْ‏.‏ وَقَالَ عُرْوَةُ عَنِ الْمِسْوَرِ وَغَيْرِهِ يُصَدِّقُ كُلُّ وَاحِدٍ مِنْهُمَا صَاحِبَهُ وَإِذَا تَوَضَّأَ النَّبِيُّ صلى الله عليه وسلم كَادُوا يَقْتَتِلُونَ عَلَى وَضُوئِهِ‏.‏
Ibn Shihab:

Mahmud bin Ar-Rabi` who was the person on whose face the Prophet (ﷺ) had ejected a mouthful of water from his family's well while he was a boy, and `Urwa (on the authority of Al-Miswar and others) who testified each other, said, "Whenever the Prophet (ﷺ) , performed ablution, his companions were nearly fighting for the remains of the water."