Sahih Muslim 372
Sahih Muslim · Book 3: The Book of Menstruation · Evidence that the Muslim does not become impure
Hudhaifa reported:
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ ، وَأَبُو كُرَيْبٍ قَالاَ حَدَّثَنَا وَكِيعٌ ، عَنْ مِسْعَرٍ ، عَنْ وَاصِلٍ ، عَنْ أَبِي وَائِلٍ ، عَنْ حُذَيْفَةَ ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم لَقِيَهُ وَهُوَ جُنُبٌ فَحَادَ عَنْهُ فَاغْتَسَلَ ثُمَّ جَاءَ فَقَالَ كُنْتُ جُنُبًا . قَالَ " إِنَّ الْمُسْلِمَ لاَ يَنْجُسُ " .
The Messenger of Allah (ﷺ) happened to meet him and he was (sexually) defiled, and he slipped away and took a bath and then came and said: I was (sexually) defiled. Upon this he (the Holy Prophet) remarked: A Muslim is never defiled.