Those are worshippers who will have “washed their robes and made them white in the blood of the Lamb. ” ​ — Rev. 7: 9, 14 - 17.
فَهٰؤُلَاءِ هُمْ عُبَّادٌ « غَسَلُوا حُلَلَهُمْ وَبَيَّضُوهَا بِدَمِ ٱلْحَمَلِ » .‏ —‏ رؤ ٧ :‏ ​ ٩ ،‏ ١٤ -‏ ١٧‏ .‏