Is it necessary to perform ghusl with water if urine or feces exceed the point of exit, and wiping is insufficient, rendering the prayer of one who has not washed invalid?

The jurists differed on the ruling of istijmar (cleaning with stones) if the excreted matter exceeds the usual place. The Hanbalis held that it is not permissible, and that water is necessary for what exceeds the usual place. However, Sheikh al-Islam Ibn Taymiyyah held it to be permissible. Whereas the Shafi'i school has a broader view, considering istijmar permissible as long as the excreted matter does not exceed the page (for defecation) or the glans (for urination), explaining that this is a widespread affliction (balwa), difficult to guard against, and that the inability to precisely control it ties the ruling to the page and the glans. Accordingly, those who stipulate water believe that the prayer is not valid by only using stones, while the Shafi'is believe their opinion is stronger due to the strength of their reasoning.