Mishkat al-Masabih
Mishkat al-Masabih 477
عَنِ ابْنِ عُمَرَ قَالَ سُئِلَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَنِ الْمَاءِ يَكُونُ فِي الْفَلَاةِ مِنَ الْأَرْضِ وَمَا يَنُوبُهُ مِنَ الدَّوَابّ وَالسِّبَاع فَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِذَا كَانَ الْمَاءُ قُلَّتَيْنِ لَمْ يَحْمِلِ الْخَبَثَ» . رَوَاهُ أَحْمد وَأَبُو دَاوُد وَالتِّرْمِذِيّ وَالنَّسَائِيّ والدارمي وَابْنُ مَاجَهْ وَفِي أُخْرَى لِأَبِي دَاوُدَ: «فَإِنَّهُ لَا ينجس»
Ibn ʿUmar said that the Messenger of Allah was asked about water in the open country, which animals and wild beasts visited. He replied: ‘When the water amounts to two qullahs, it does not carry impurity.’
Aḥmad, Abū Dāwūd, al-Tirmidhī, al-Nasāʾī, al-Dārimī, and Ibn Mājah transmitted it. Another version from Abū Dāwūd says: ‘It does not become impure.’