Sahih al-Bukhari, Book 77, Hadith 50 (In-Book) ⓘ
Narrated Thabit: I heard Ibn Az-Zubair delivering a sermon, saying, "Muhammad said, 'Whoever wears silk in this world, shall not wear it in the Hereafter."
حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا حَمَّادُ بْنُ زَيْدٍ، عَنْ ثَابِتٍ، قَالَ سَمِعْتُ ابْنَ الزُّبَيْرِ، يَخْطُبُ يَقُولُ قَالَ مُحَمَّدٌ صلى الله عليه وسلم " مَنْ لَبِسَ الْحَرِيرَ فِي الدُّنْيَا لَمْ يَلْبَسْهُ فِي الآخِرَةِ " .
also referenced under: Hadith 5833 (DarusSalam) & Volume 7, Book 72, Hadith 724 (USC-MSA)