Bukhari :: Book 7 :: Volume 72 :: Hadith 720

Narrated Abu 'Uthman:

While we were with 'Utba. 'Umar wrote to us: The Prophet said, "There is none who wears silk in this world except that he will wear nothing of it in the Hereafter." ' Abu 'Uthman pointed out with his middle and index fingers.

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