Revelation 7:9-14

YLT(i) 9 After these things I saw, and lo, a great multitude, which to number no one was able, out of all nations, and tribes, and peoples, and tongues, standing before the throne, and before the Lamb, arrayed in white robes, and palms in their hands, 10 and crying with a great voice, saying, `The salvation is to Him who is sitting upon the throne—to our God, and to the Lamb!' 11 And all the messengers stood around the throne, and the elders and the four living creatures, and they fell upon their face, and bowed before God, 12 saying, `Amen! the blessing, and the glory, and the wisdom, and the thanksgiving, and the honour, and the power, and the strength, are to our God—to the ages of the ages! Amen!'
13 And answer did one of the elders, saying to me, `These, who have been arrayed with the white robes—who are they, and whence came they?' 14 and I have said to him, `Sir, thou hast known;' and he said to me, `These are those who are coming out of the great tribulation, and they did wash their robes, and they made their robes white in the blood of the Lamb;