Muhammad bin 'Amr bin 'Alqama محمد بن عمرو بن علقمة · The Book on Purification

I was with the Prophet on a journey. The Prophet had to relieve himself, so he went far away."

Allah's Messenger said: "If it were not that it would be difficult on my nation, then I would have ordered them to use the Siwak for each prayer."

Allah's Messenger said: "Wudu is (required) from what fire has touched, even if it be a piece of cheese."

"I asked the Prophet about Al-Madhi. He said: "For Al-Madhi is Wudu, and for AI-Mani is Ghusl."