"I heard 'Uthman say: 'Avoid Khamr for it is the mother of all evils. There was a man among those who came before you who was a devoted worshipper and used to stay away from people.'" And he mentioned something similar. He said: "Avoid Khamr for, by Allah, it can never coexist with Faith, but soon one of them will expel the other."
Sunan an-Nasa'i Book 51, Hadith 129