Sunan Ibn Majah
598
Daif+2

Abu Ayyub Al-Ansari narrated that: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

DaifAl-Albani
DaifMuhammad Fouad Abd al-Baqi