Sunan At-Tirmidhi

Abu Hurairah narrated that :the Prophet met him while he was Junub. He said: ""[So I slipped away from him - meaning:] I withdrew - to perform Ghusl. Then he returned, so he said: 'Where have you been?' Or: 'Where did you go?' I replied: 'I was Junub.' So he said: 'Indeed the believer is not defiled