Sahih Bukhari Volume 1, Book 5, Hadith 285

حَدَّثَنَا عَيَّاشٌ، قَالَ حَدَّثَنَا عَبْدُ الأَعْلَى، حَدَّثَنَا حُمَيْدٌ، عَنْ بَكْرٍ، عَنْ أَبِي رَافِعٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ لَقِيَنِي رَسُولُ اللَّهِ صلى الله عليه وسلم وَأَنَا جُنُبٌ، فَأَخَذَ بِيَدِي، فَمَشَيْتُ مَعَهُ حَتَّى قَعَدَ فَانْسَلَلْتُ، فَأَتَيْتُ الرَّحْلَ، فَاغْتَسَلْتُ ثُمَّ جِئْتُ وَهْوَ قَاعِدٌ فَقَالَ ‏"‏ أَيْنَ كُنْتَ يَا أَبَا هِرٍّ ‏"‏ فَقُلْتُ لَهُ‏.‏ فَقَالَ ‏"‏ سُبْحَانَ اللَّهِ يَا أَبَا هِرٍّ إِنَّ الْمُؤْمِنَ لاَ يَنْجُسُ ‏"

Narrated By Abu Huraira : Allah's Apostle came across me and I was Junub 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 AbuHuraira! Where have you been?' I told him about it The Prophet said, "Subhan Allah! O Abu Huraira! A believer never becomes impure."