Musnad Ahmad 30:2955

Yahya narrated to us, from Humayd, who said: Bakr ibn Abdullah narrated to us, from Abu Rafi’, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) met me while he was on one of the paths of Medina. I slipped away and went and performed ghusl (ritual bath), then I came back. He said: "Where were you?" I said: You met me while I was in a state of janabah (major ritual impurity), and I disliked sitting with you while I was not in a state of purity. He said: "Indeed, the Muslim does not become impure."