كتاب اللباس
Read the English translation first, with the original Arabic directly underneath.
Narrated Anas bin Malik:
The Prophet (ﷺ) said, Whoever wears silk in this world shall not wear it in the Hereafter."
مَنْ لَبِسَ الْحَرِيرَ فِي الدُّنْيَا فَلَنْ يَلْبَسَهُ فِي الآخِرَةِ