أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا حَمَّادٌ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، أَنَّ أَعْرَابِيًّا، بَالَ فِي الْمَسْجِدِ فَقَامَ إِلَيْهِ بَعْضُ الْقَوْمِ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏
"‏ دَعُوهُ لاَ تُزْرِمُوهُ ‏"‏ ‏.‏ فَلَمَّا فَرَغَ دَعَا بِدَلْوٍ فَصَبَّهُ عَلَيْهِ ‏.‏ قَالَ أَبُو عَبْدِ الرَّحْمَنِ يَعْنِي لاَ تَقْطَعُوا عَلَيْهِ ‏.‏

It was narrated from Anas that a Bedouin urinated in the Masjid, and some of the people went after him, but the Messenger of Allah (ﷺ) said: "Leave him and do not restrain him." When he had finished he called for a bucket (of water) and poured it over it.

Abu 'Abdur-Rahman (An-Nasa'i) said: "Meaning: 'Do not interrupt him.'"

The author will cite this narration again in No. 330 as a possible proof for setting the minimum, since it mentions "a bucket" as if this is the minium amount required.