Revelation 7:13-14

 "And behold, I am coming quickly. 

Blessed is he who heeds the words of the prophecy of this book."     

Revelation 22:7  NASB

Then one of the elders asked me, "These in white robes--who are they and where did they come from?" I answered, "Sir, you know." And he said, "These are they who have come out of the great tribulation; they have washed their robes and made them white in the blood of the Lamb."

These in white robes 
Revelation 3:4  "Yet you have a few people in Sardis who have not soiled their clothes. They will walk with me, dressed in white, for they are worthy."
Revelation 6:11  Then each of them was given a white robe, and they were told to wait a little longer, until the full number of their fellow servants, their brothers and sisters, were killed just as they had been.

they have washed their robes 
Revelation 22:14  "Blessed are those who wash their robes, that they may have the right to the tree of life and may go through the gates into the city." 

and made them white in the blood of the Lamb 
Hebrews 9:14  How much more, then, will the blood of Christ, who through the eternal Spirit offered himself unblemished to God, cleanse our consciences from acts that lead to death, so that we may serve the living God!
1 John 1:7  But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus, his Son, purifies us from all sin.
Revelation 12:11  "They triumphed over him by the blood of the Lamb and by the word of their testimony; they did not love their lives so much as to shrink from death."

Scriptures taken from the Holy Bible, New International Version® NIV®, Copyright© 1973, 1978, 1984, 2011 by Biblica, Inc.® Used by permission. All rights reserved worldwide. 
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