Biography of Salih al-Ansari
US: Salih al-Ansari al-Salmi.
He is mentioned in a hadith of Abu Sa'id al-Khudri.
Yunus b. Bukayr, from Ibn Ishaq, from Sa'id b. 'Abd al-Rahman b. Abu Sa'id al-Khudri, from his father, from his grandfather Abu Sa'id, said: We went out with the Messenger of Allah ﷺ to the mosque of Banu 'Amr b. 'Awf. We passed by the village of Banu Salim, and he called out to a man from his companions, named: Salih. He came out to him, and the Messenger of Allah ﷺ took his hand, until he entered the mosque. Salih then released his hand from the hand of the Messenger of Allah ﷺ and went to a part of the wall, and entered it. He then washed, and came out, while the Messenger of Allah was at the door of the mosque, and said to him: 'Where did you go, O Salih?', he said: I was called out to, and I was with a woman, speaking to her. When I heard your voice, I responded to you. When I entered the mosque, I disliked to bring him in until he had washed, so the Messenger of Allah ﷺ said: 'Water is water'.
It was narrated by Dhakwan from Abu Sa'id, without mentioning the man's name, and also by Abu Hurairah and Ibn 'Abbas.
It was narrated by Abu Naim and Abu Musa.