Sahih Al Bukhari (285)

عن أبي هريرة قال: لقيني رسول الله صلى الله عليه وسلم وأنا جنب، فأخذ بيدي، فمشيت معه حتى قعد، فانسللت، فأتيت الرحل، فاغتسلت ثم جئت وهو قاعد، فقال: (أين كنت يا أبا هر). فقلت له، فقال: (سبحان الله يا أبا هر، إن المؤمن لا ينجس).

Abu Hurayrah (may Allah be pleased with him) narrated that Allah’s Messenger (peace be upon him) came across me and I was Junub (in the state of major ritual impurity). He took my hand and I went along with him till he sat down I slipped away, went home and took a bath. When I came back, he was still sitting there. He then said to me: "O Abu Hurayrah! Where have you been?" I told him about it. The Prophet (peace be upon him) said: "Subhan Allah! O Abu Hurayrah! A believer never becomes impure."