Revelation 7:14

And I have said to him, "My lord, you know." And he said to me, "These are those who come out of the great tribulation; and they washed their robes, and made them white in the blood of the Lamb.

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 cleanses us from all sin.

Hebrews 9:14

how much more shall the blood of Christ, Who through the Eternal Spirit offered Himself without blemish to God, cleanse your conscience from dead works to serve the living God?

Revelation 1:5

and from Jesus Christ, the faithful Witness, the First-born of the dead, and the Ruler of the kings of the earth. To Him Who loveth, and loosed us from our sins in His own blood,

Revelation 22:14

Happy are those who wash their robes, that they may have the right to the tree of life, and may enter by the gates into the city.

Matthew 24:21

for then will be great tribulation, such as has not happened from the beginning of the world until now; no, nor ever shall be.

John 13:8-14

Peter says to Him, "Thou shalt never wash my feet!" Jesus answered him, "If I wash you not, you have no part with Me."

John 16:33

These things have I spoken to you, that in Me ye may have peace. In the world ye have tribulation; but be of good cheer; I have overcome the world."

Acts 14:22

confirming the souls of the disciples, exhorting them to abide in the faith, and that through many tribulations we must enter into the Kingdom of God.

Romans 5:3

And not only so, but we also rejoice in our tribulations; knowing that tribulation works out patience;

1 Corinthians 6:11

And such were some of you; but ye were washed, but ye were sanctified, but ye were justified in the name of the Lord Jesus, and in the Spirit of our God.

Ephesians 5:26-27

that He might sanctify it, having cleansed it by the washing of the water in the word,

2 Thessalonians 1:4

so that we ourselves glory in you in the assemblies of God, for your patience and faith in all your persecutions and tribulations which ye endure;

Hebrews 13:12

Wherefore, Jesus also, that He might sanctify the people through His own blood, suffered without the gate.

1 Peter 1:19

but with the precious blood of Christ, as of a lamb without blemish and without spot;

Revelation 2:9

"I know your tribulation, and your poverty (but you are rich), and the blasphemy of those who say they are Jews, and are not, but are a synagogue of Satan.

Revelation 5:9

And they sing a new song, saying, "Worthy art Thou to take the book, and to open its seals; because Thou wast slain, and didst redeem to God, by Thy blood, some of every tribe, and tongue, and people, and nation;

Revelation 6:9-11

And, when He opened the fifth seal, I saw, underneath the altar, the souls of those who had been slain because of the word of God, and because of the testimony which they were holding.

Revelation 12:11

and they overcame him because of the blood of the Lamb, and because of the word of their testimony, and they loved not their soul, even to death.

Revelation 15:2

And I saw as it were a glassy sea mingled with fire; and those who were victorious over the beast, and over his image, and over the number of his name, standing by the glassy sea, having harps of God.

Revelation 17:6

And I saw the woman drunken with the blood of the saints, and with the blood of the martyrs of Jesus. And, seeing her, I wondered with great wonder.

Treasury of Scripture Knowledge

Summary

And I said unto him, Sir, thou knowest. And he said to me, These are they which came out of great tribulation, and have washed their robes, and made them white in the blood of the Lamb.

General references

Bible References

And have

Revelation 1:5
and from Jesus Christ, the faithful Witness, the First-born of the dead, and the Ruler of the kings of the earth. To Him Who loveth, and loosed us from our sins in His own blood,
John 13:8
Peter says to Him, "Thou shalt never wash my feet!" Jesus answered him, "If I wash you not, you have no part with Me."
1 Corinthians 6:11
And such were some of you; but ye were washed, but ye were sanctified, but ye were justified in the name of the Lord Jesus, and in the Spirit of our God.
Ephesians 5:26
that He might sanctify it, having cleansed it by the washing of the water in the word,
Hebrews 9:14
how much more shall the blood of Christ, Who through the Eternal Spirit offered Himself without blemish to God, cleanse your conscience from dead works to 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 cleanses us from all sin.

The blood

Revelation 5:9
And they sing a new song, saying, "Worthy art Thou to take the book, and to open its seals; because Thou wast slain, and didst redeem to God, by Thy blood, some of every tribe, and tongue, and people, and nation;
Revelation 12:11
and they overcame him because of the blood of the Lamb, and because of the word of their testimony, and they loved not their soul, even to death.
Hebrews 13:12
Wherefore, Jesus also, that He might sanctify the people through His own blood, suffered without the gate.
1 Peter 1:19
but with the precious blood of Christ, as of a lamb without blemish and without spot;

General references

Matthew 5:4
"Happy are those who mourn: because they shall be comforted,