What are the reasons the jurists stipulated the removal of impurity in two cases, despite the existence of hadiths that might be understood otherwise: the removal of impurity from the body before performing ghusl for janabah, and the removal of harm/filth from the private parts of a woman with irregular bleeding (mustahadah) or a person with urinary incontinence (sahib al-sils)?

Those who argue for the necessity of removing impurity from the body before performing ghusl explain that if water flows over an impurity, it becomes altered, and therefore, it does not purify the contaminated area. This is because pure water (al-ma' al-tahur) is a condition for purification, and they believe that achieving both purifications simultaneously is a matter of dispute.

As for the menstruating woman washing her private parts from blood, this is not a condition for the validity of ablution (wudu'), but rather it falls under the category of istinja' (cleansing oneself after defecation or urination), and the obligation to renew the washing when blood appears or the bandage moves.