Sunan Ibn Majah
The Book of Purification and its Sunnah — Hadith #332
حَدَّثَنَا هِشَامُ بْنُ عَمَّارٍ، حَدَّثَنَا يَحْيَى بْنُ حَمْزَةَ، حَدَّثَنِي عُتْبَةُ بْنُ أَبِي حَكِيمٍ، حَدَّثَنِي طَلْحَةُ بْنُ نَافِعٍ، حَدَّثَنِي أَبُو أَيُّوبَ الأَنْصَارِيُّ، أَنَّ النَّبِيَّ ـ صلى الله عليه وسلم ـ قَالَ " الصَّلَوَاتُ الْخَمْسُ وَالْجُمُعَةُ إِلَى الْجُمُعَةِ وَأَدَاءُ الأَمَانَةِ كَفَّارَةٌ لِمَا بَيْنَهَا " . قُلْتُ وَمَا أَدَاءُ الأَمَانَةِ قَالَ " غُسْلُ الْجَنَابَةِ فَإِنَّ تَحْتَ كُلِّ شَعَرَةٍ جَنَابَةً " .
The Prophet said: “The five daily prayers, from one Friday to the next, and fulfilling the trust are all expiation for whatever (sins) come between them.” I said: “What is fulfilling the trust?” He said: Having a bath to cleanse oneself from sexual impurity, for under every hair there is the state of sexual impurity.”
Chain of Narration (Isnad)