Muwatta Malik, Book 49, Hadith 1712 (In-Book)

Yahya related to me from Malik that Sadaqa ibn Yasar said, "I asked Said ibn al-Musayyab about wearing a ring. He said, 'Wear it, and tell people that I gave you that decision.' "

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ صَدَقَةَ بْنِ يَسَارٍ، أَنَّهُ قَالَ سَأَلْتُ سَعِيدَ بْنَ الْمُسَيَّبِ عَنْ لُبْسِ الْخَاتَمِ، فَقَالَ الْبَسْهُ وَأَخْبِرِ النَّاسَ، أَنِّي أَفْتَيْتُكَ بِذَلِكَ ‏.‏

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also referenced under: Book 49, Hadith 38 (USC-MSA)