Muwatta Malik, Book 31, Hadith 1350 (In-Book)

Yahya related to me from Malik that he had heard that Uthman ibn Affan forbade hoarding.

وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ عُثْمَانَ بْنَ عَفَّانَ، كَانَ يَنْهَى عَنِ الْحُكْرَةِ، ‏.‏

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also referenced under: Book 31, Hadith 58 (USC-MSA)