Mas’ala 199الأمShafi'ivol. 1, p. 37vol. 1, p. 37 لِأَنَّهُ لَوْ جَهِدَ لَمْ يُنَقِّهِ بِغَيْرِ مَاءٍ. Read the whole chapterCopy with source On the map: PurityCompare