Chapter on Water and Its Rules
Tahdhīb al-Aḥkām|Volume 1|Book 1|Chapter 21
مُحَمَّدُ بْنُ أَحْمَدَ بْنِ يَحْيَى عَنْ إِبْرَاهِيمَ بْنِ إِسْحَاقَ عَنْ مُحَمَّدِ بْنِ سُلَيْمَانَ الدِّيلَمِيِّ عَنْ أَبِيهِ قَالَ: سَأَلْتُ أَبَا عَبْدِ اللهِ عَلَيْهِ السَّلَامُ عَنِ الْبِئْرِ يَكُونُ إِلَى جَنْبِهَا الْكُنِيفُ؟ فَقَالَ لِي: إِنَّ مَجْرَى الْعُيُونِ كُلَّهَا مَعَ مَهَبِّ الشَّمَالِ، فَإِذَا كَانَتِ الْبِئْرُ النَّظِيفَةُ فَوْقَ الشَّمَالِ وَالْكُنِيفُ أَسْفَلَ مِنْهَا لَمْ يَضُرَّهَا إِذَا كَانَ بَيْنَهُمَا أَذْرُعٌ. وَإِنْ كَانَ الْكُنِيفُ فَوْقَ النَّظِيفَةِ فَلَا أَقَلَّ مِنِ اثْنَيْ عَشَرَ ذِرَاعًا، وَإِنْ كَانَتْ تُجَاهَهَا بِحِذَاءِ الْقِبْلَةِ وَهُمَا مُسْتَوِيَانِ فِي مَهَبِّ الشَّمَالِ فَسَبْعَةُ أَذْرُعٍ.
Muhammad ibn Ahmad ibn Yahya, from Ibrahim ibn Ishaq, from Muhammad ibn Sulayman Al-Daylami, from his father, who said:
I asked Abu Abdullah عليه السلام about a well that is located near a toilet. Imam عليه السلام said to me: "The flow of all underground water follows the direction of the north wind. If the clean well is situated above the north and the toilet is below it, then it does not harm the well as long as there is a specified distance between them. And if the toilet is above the clean well, then the distance should not be less than twelve cubits. However, if the toilet is directly opposite the well, facing the Qiblah, and they are at the same level along the path of the north wind, then the distance should be seven cubits."
- Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 1, p. 434
- Ṣaḥīḥ al-Tahdhīb, p. 18