(2) باب التَّوْقِيتِ فِي الْمَاءِ
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:
"Do not restrain him." When he had finished he called from a bucket (of water) and poured over it.
Reference: Sunan an-Nasa'i 329
In-book reference: Book 2, Hadith 5
English translation: Vol. 1, Book 2, Hadith 330