Muwatta Malik, Book 27, Hadith 1078 (In-Book)

Yahya related to me from Malik from Ibn Shihab from Qabisa ibn Dhu'ayba that Umar ibn al-Khattab gave the grandfather "what people give him today."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ قَبِيصَةَ بْنِ ذُؤَيْبٍ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، فَرَضَ لِلْجَدِّ الَّذِي يَفْرِضُ النَّاسُ لَهُ الْيَوْمَ ‏.‏

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also referenced under: Book 27, Hadith 2 (USC-MSA)