Musannaf Ibn Abi Shayba 36:320

Ibn Idris narrated to us, from Husayn, from Salim, from Jabir, who said: The people were struck by thirst on the day of al-Hudaybiyyah. He said: The people rushed toward the Messenger of Allah (ﷺ). He said: So he placed his hand into the water skin, and I saw the water like springs. He said: I said, "How many were you?" He said, "If we had been one hundred thousand, it would have sufficed us; we were fifteen hundred."