Musnad Ahmad 1034:175

Waki’ narrated to us, Yazid bin Ibrahim narrated to us, from Ibn Sirin, who said: The Prophet, may Allah bless him and grant him peace, went out and Hudhayfah met him, so he turned away from him and performed ghusl (ritual bath). Then he came, and he (the Prophet) said: "What is the matter with you?" He said: "O Messenger of Allah, I was in a state of janabah (major ritual impurity)." The Messenger of Allah, may Allah bless him and grant him peace, said: "Indeed, the Muslim does not become impure."