Allah's Messenger (ﷺ) said, "None wears silk in this world, but he who will have no share in the Hereafter."
Sahih al-Bukhari Book 77, Hadith 52
← Previous Hadith I heard `Umar saying, "The Prophet (ﷺ) said, 'Whoever wears silk in this world, shall not wear it in the Hereafter."

This hadith is also narrated through 'Umar ibn al-Khattab.

Sahih al-Bukhari Book 77, Hadith 51 Next Hadith → The Prophet (ﷺ) was given a silk garment as a gift and we started touching it with our hands and admiring it. On that the Prophet (ﷺ) said, "Do you wonder at this?" We said, "Yes." He said, "The handkerchiefs of Sa`d bin Mu`adh in Paradise are better than this."

Sahih al-Bukhari Book 77, Hadith 53