John Wesley on Revelation 7:14

My lord - Or, my master; a common term of respect. So Zechariah, likewise, bespeaks the angel, Zec 1:9; 4:4; 6:4. Thou knowest - That is, I know not; but thou dost. These are they - Not martyrs; for these are not such a multitude as no man can number. But as all the angels appear here, so do all the souls of the righteous who had lived from the beginning of the world. Who come - He does not say, who did come; but, who come now also: to whom, likewise, pertain all who will come hereafter. Out of great affliction - Of various kinds, wisely and graciously allotted by God to all his children. And have washed their robes - From all guilt. And made them white - In all holiness. By the blood of the Lamb - Which not only cleanses, but adorns us also.