Chapter 1: Purification (Kitab Al-Taharah)
Abu Dharr said: A few goats got collected with the Messenger of Allah (ﷺ). He said: Abu Dharr, drive them to the wood. I drove them to Rabadhah (a place near Medina). I would have sexual defilement (during my stay there) and I would remain (in this condition) for five or six days. Then I came to the Messenger of Allah (ﷺ). He said: O Abu Dharr. I kept silence. He then said: May your mother bereave you, Abu Dharr: woe be to your mother. He then called a black slave-girl for me. She brought a vessel which contained water. She then concealed me by drawing a curtain and I concealed myself behind a she-camel, and took a bath. I felt as if I had thrown away a mountain from me. He said: Clean earth is a means for ablution for a Muslim, even for ten years (he does not find water); but when you find water, you should make it touch your skin, for that is better. The version of Musaddad has: "the goats (were collected) from the alms," and the tradition reported by 'Amr is complete.
Sunan Abi Dawud 332