Revelation Chapter 7 has no mention of the seals. The sixth seal is in Revelation 6:12, but the seventh seal is not open until Revelation 8:1.

This chapter answers the questions of who will be able to stand the great wrath of God. Revelation 6:17 For the great day of his wrath is come; and who shall be able to stand?

Revelation 7:1 And after these things I saw four angels standing on the four corners of the earth, holding the four winds of the earth, that the wind should not blow on the earth, nor on the sea, nor on any tree.

After these things, are the sixth seals that have been open in Chapter 6. The four angels have control over the winds. When the winds of the earth are stop the rains also stop and causes famine on the earth (Revelation 6:5). The two witness show up at the beginning of the tribulation and they have power to stop it from raining for 31/2 years. Revelation 11:6 These have power to shut heaven, that it rain not in the days of their prophecy: and have power over waters to turn them to blood, and to smite the earth with all plagues, as often as they will.
North, South, East and West are the four corners of the earth where the four angels are standing. The earth is round and there is night and day at the same time on the earth. This scientific fact has been in the scriptures many years before Columbus discovered America.
Isaiah 40:22 It is he that sitteth upon the circle of the earth, and the inhabitants thereof are as grasshoppers; that stretcheth out the heavens as a curtain, and spreadeth them out as a tent to dwell in:

Revelation 7:2 And I saw another angel ascending from the east, having the seal of the living God: and he cried with a loud voice to the four angels, to whom it was given to hurt the earth and the sea,
Revelation 7:3 Saying, Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads.

God is using angels to carry out His will like He did when He was dealing with Israel.

Revelation 8:7 The first angel sounded, and there followed hail and fire mingled with blood, and they were cast upon the earth: and the third part of trees was burnt up, and all green grass was burnt up.
Revelation 7:4 And I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand of all the tribes of the children of Israel.

An angel seals the remnant like the description in Ezekiel. They were marked in the forehead with ink. They were marked with the name of God. Revelation 14:1 And I looked, and, lo, a Lamb stood on the mount Sion, and with him an hundred forty and four thousand, having his Father's name written in their foreheads. Ezekiel 9:4 And the LORD said unto him, Go through the midst of the city, through the midst of Jerusalem, and set a mark upon the foreheads of the men that sigh and that cry for all the abominations that be done in the midst thereof.

Revelation 7:5 Of the tribe of Juda were sealed twelve thousand. Of the tribe of Reuben were sealed twelve thousand. Of the tribe of Gad were sealed twelve thousand.
Revelation 7:6 Of the tribe of Aser were sealed twelve thousand. Of the tribe of Nepthalim were sealed twelve thousand. Of the tribe of Manasses were sealed twelve thousand.
Revelation 7:7 Of the tribe of Simeon were sealed twelve thousand. Of the tribe of Levi were sealed twelve thousand. Of the tribe of Issachar were sealed twelve thousand.
Revelation 7:8 Of the tribe of Zabulon were sealed twelve thousand. Of the tribe of Joseph were sealed twelve thousand. Of the tribe of Benjamin were sealed twelve thousand.
There were twelve thousand from each tribe and there were 144,000 sealed. These are virgin, men who have not been defiled with women (Revelation 14:4). Their mission is to preach the gospel of the kingdom so the end of the tribulation will come.
Matthew 24:14 And this gospel of the kingdom shall be preached in all the world for a witness unto all nations; and then shall the end come.

Juda is the first in order of God’s chose and not according to the first born which was Reuben.
Notice the 12 tribes that are sealed are not the 12 tribes named in Genesis 49 nor the 12 tribes named in Numbers 1:5-16. Joseph has two sons, Ephraim and Manasseh. These two sons replaced Joseph which was sold into slavery and Levi which was the priestly tribe. The sealed tribes in the tribulation period has Joseph and Levi place back into the 12 tribes and Ephraim and Dan are take out. Levi is added back into the 12 tribes because during the reign of Jesus Christ on the earth all of the 12 tribes will be priest.
Exodus 19:6 And ye shall be unto me a kingdom of priests, and an holy nation.  These are the words which thou shalt speak unto the children of Israel.
Ephraim and Dan are not sealed in the tribulation period. They are in the tribulation period but they are not preserved because they joined themselves to idols.
Hose 4:17 Ephraim is joined to idols: let him alone. Isaiah 49:6 And he said, It is a light thing that thou shouldest be my servant to raise up the tribes of Jacob, and to restore the preserved of Israel: I will also give thee for a light to the Gentiles, that thou mayest be my salvation unto the end of the earth.
In the Old Testament, the tribe of Dan is involved in things that are bad, such as Bail worshippers. In Genesis 49:17, Dan is called a serpent and in Deut 33:22 he is called a lion. Satan is also called a serpent and a lion, so for these reasons Dan is not sealed during the tribulation period.

Revelation 7:9 After this I beheld, and, lo, a great multitude, which no man could number, of all nations, and kindreds, and people, and tongues, stood before the throne, and before the Lamb, clothed with white robes, and palms in their hands;
The first group John sees is the sealing of the 144,000 from the 12 tribes of Israel on earth. In this group are the believing remnant of Israel that have endured and not taken the mark of the beast. Revelation 14:1 And I looked, and, lo, a Lamb stood on the mount Sion, and with him an hundred forty and four thousand, having his Father's name written in their foreheads. We see that the 144,000 have been rapture and are before the throne. The second group were all the people that have not take the mark of the beast and have been rapture and are also before the throne. The white robes are given to the martyrs and represents human righteousness because they have endured unto death. These are the ones that will attend the marriage super of the lamb. Revelation 19:7 Let us be glad and rejoice, and give honour to him: for the marriage of the Lamb is come, and his wife hath made herself ready. Revelation 19:8 And to her was granted that she should be arrayed in fine linen, clean and white: for the fine linen is the righteousness of saints.
Revelation 3:12 Him that overcometh will I make a pillar in the temple of my God, and he shall go no more out: and I will write upon him the name of my God, and the name of the city of my God, which is new Jerusalem, which cometh down out of heaven from my God: and I will write upon him my new name.
Revelation 6:11 And white robes were given unto every one of them; and it was said unto them, that they should rest yet for a little season, until their fellowservants also and their brethren, that should be killed as they were, should be fulfilled.

Revelation 7:10 And cried with a loud voice, saying, Salvation to our God which sitteth upon the throne, and unto the Lamb.
Revelation 7:11 And all the angels stood round about the throne, and about the elders and the four beasts, and fell before the throne on their faces, and worshipped God,
Revelation 7:12 Saying, Amen: Blessing, and glory, and wisdom, and thanksgiving, and honour, and power, and might, be unto our God for ever and ever. Amen.
Revelation 7:13 And one of the elders answered, saying unto me, What are these which are arrayed in white robes? and whence came they?
Revelation 7:14 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.
These are the martyrs that have not taken the mark of the beast and have been take from earth to heaven during the tribulation period. They have endured until death. These are the saints that will be part of the armies that returns to earth to reign with the Lord Jesus Christ for 1000 years.
Revelation 20:4 And I saw thrones, and they sat upon them, and judgment was given unto them: and I saw the souls of them that were beheaded for the witness of Jesus, and for the word of God, and which had not worshipped the beast, neither his image, neither had received his mark upon their foreheads, or in their hands; and they lived and reigned with Christ a thousand years.

Revelation 7:15 Therefore are they before the throne of God, and serve him day and night in his temple: and he that sitteth on the throne shall dwell among them.

This temple is on earth in the kingdom. In heaven there is no night.

Revelation 7:16 They shall hunger no more, neither thirst any more; neither shall the sun light on them, nor any heat.
Revelation 7:17 For the Lamb which is in the midst of the throne shall feed them, and shall lead them unto living fountains of waters: and God shall wipe away all tears from their eyes. These saints are not the Body of Christ (the church) because our positions will be in heaven after Satan and his angels have been cast out at the half waypoint of the tribulation period. These saints are the ones that have been martyred for a witness of Jesus and will take part in the first resurrection.Revelation:20:6: Blessed and holy is he that hath part in the first resurrection: on such the second death hath no power, but they shall be priests of God and of Christ, and shall reign with him a thousand years.

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