Is it necessary to stop the flow of water while purifying impurity from the body or clothing?

The question is unclear. However, if the intent is to ask whether it is a condition for water to come into contact with the impurity for its removal, then this is the view of many scholars. Some, however, do not stipulate this, but rather say that what matters is the removal of the impurity, whether the water comes into contact with the impurity or the impurity comes into contact with the water. Al-Nawawi extensively discussed this principle in his Sharh al-Muhadhdhab.