Sunan Ibn Mājah 528✓ 5Sahih
حَدَّثَنَا أَحْمَدُ بْنُ عَبْدَةَ، أَنْبَأَنَا حَمَّادُ بْنُ زَيْدٍ، حَدَّثَنَا ثَابِتٌ، عَنْ أَنَسٍ، أَنَّ أَعْرَابِيًّا، بَالَ فِي الْمَسْجِدِ فَوَثَبَ إِلَيْهِ بَعْضُ الْقَوْمِ فَقَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " لاَ تُزْرِمُوهُ " . ثُمَّ دَعَا بِدَلْوٍ مِنْ مَاءٍ فَصَبَّ عَلَيْهِ .
It was narrated from Anas bin Malik that: A Bedouin urinated in the mosque, and some of the people rushed at him. The Messenger of Allah said: "Do not interrupt him." Then he called for a bucket of water and poured it over (the urine)