Muwatta Malik, Book 36, Hadith 1433 (In-Book)

Malik related to me from Abu'z-Zinad from al-Araj from Abu Hurayra that the Messenger of Allah, may Allah bless him and grant him peace, said, "Excess water is not withheld in order to prevent herbage from growing."

وَحَدَّثَنِي مَالِكٌ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ لاَ يُمْنَعُ فَضْلُ الْمَاءِ لِيُمْنَعَ بِهِ الْكَلأُ ‏" ‏ ‏.‏

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also referenced under: Book 36, Hadith 29 (USC-MSA)