I would state the great tribulation is in the days of the reign of the beast. The beast and his armies will cause and be the cause of astounding devastation on earth. So much so unless those days were cut short by God no one would survive.
I would state a sign that can't be mistaken for that beginning is REV 11. 1260 days as I read and the beast is in Jerusalem as he is allowed to overpower and kill Gods appointed witnesses when no one else could and God takes them alive up to heaven as the "whole world" looks on. A testimony for all peoples. The world will say "who can make war with the beast" as he did what no one else could. Overpowered Gods two witnesses. This adds to the lie and deception of the beasts false witness as judgment from God enters the world. If anyone in the world at that time really has any faith to believe they will believe through those signs given. A final last warning. As a just God warns and warns upfront. Then the powerful delusion given through the beast enters the whole world to deceive those who love to do evil and refuse to believe and repent so that they will be condemned. Many who hold firmly to the testimony of Jesus will be put to the sword as we read of those raised to life in the 1st resurrection.
Now it's clear about what was understood and taught about the resurrection of the righteous on the last day. That God will sift from the ends of the heavens and earth even catching up those who belong to God and are still alive on earth on that last day gathering. The resurrection and gathering of us all and all are clothed with immortality on that last day. Therefore those not raised in the 1st resurrection must be those who suffer.
Matthew 25:31 When the Son of man shall come in his glory, and all the holy angels with him, then shall he sit upon the throne of his glory: 32 And before him shall be gathered all nations: and he shall separate them one from another, as a shepherd divideth his sheep from the goats: 33 And he shall set the sheep on his right hand, but the goats on the left. 34 Then shall the King say unto them on his right hand, Come, ye blessed of my Father, inherit the kingdom prepared for you from the foundation of the world:
John 5:27 And hath given him authority to execute judgment also, because he is the Son of man. 28 Marvel not at this: for the hour is coming, in the which all that are in the graves shall hear his voice, 29 And shall come forth; they that have done good, unto the resurrection of life; and they that have done evil, unto the resurrection of damnation.
2 Corinthians 5:10 For we must all appear before the judgment seat of Christ; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad.
2 Thessalonians 1:1 Paul, and Silvanus, and Timotheus, unto the church of the Thessalonians in God our Father the Lord Jesus Christ: 2 Grace unto you, and peace, from God our Father and the Lord Jesus Christ. 3 We are bound to thank God always for you, brethren, as it is meet, because that your faith groweth exceedingly, and the charity of every one of you all toward each other aboundeth; 4 So that we ourselves glory in you in the churches of God for your patience and faith in all your persecutions and tribulations that ye endure: 5 Which is a manifest token of the righteous judgment of God, that ye may be counted worthy of the kingdom of God, for which ye also suffer: 6 Seeing it is a righteous thing with God to recompense tribulation to them that trouble you; 7 And to you who are troubled rest with us, when the Lord Jesus shall be revealed from heaven with his mighty angels, 8 In flaming fire taking vengeance on them that know not God, and that obey not the gospel of our Lord Jesus Christ: 9 Who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power; 10 When he shall come to be glorified in his saints, and to be admired in all them that believe (because our testimony among you was believed) in that day.
Rev 11:18 And the nations were angry, and thy wrath is come, and the time of the dead, that they should be judged, and that thou shouldest give reward unto thy servants the prophets, and to the saints, and them that fear thy name, small and great; and shouldest destroy them which destroy the earth.
Rev 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. 5 But the rest of the dead lived not again until the thousand years were finished. This is the first resurrection. 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.
Rev 20:11 And I saw a great white throne, and him that sat on it, from whose face the earth and the heaven fled away; and there was found no place for them. 12 And I saw the dead, small and great, stand before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works.
When I read all the scriptures of Jesus sitting at the right hand of God and these scriptures that speak about the judgement of Christ, the Great White throne judgement where God is sitting on the throne and the books that are opened, Matthew 25:31-34; John 5:27-29; 2 Corinthians 5:10; Rev 11:18; Rev 20:4-6; Rev 20:11, 12, this makes me believe that at the Great White Throne judgement God will be sitting on His throne and Jesus is there seated at Gods right hand now on His throne of glory. All (saints and sinners) have been called from their graves (one resurrection) and the sheep are then separated from the goats as the sheep, being those of God and His Son will stand before the judgement seat of Christ as they have been given their new glorified bodies and their names found in the book of life. They will then be judged for their good works they did as being the continued works of the Lord being in Gods will and receive their crown rewards and their inheritance of the Kingdom of God. The goats being those who are not Gods will be judged out of the other books and their judgement is that of rejecting God and His Son and their punishment is being cast into the lake of fire.
Scripture never speaks of two resurrections, but only one resurrection, John 5:28, 29 and a second death being that of death and hell being cast into the lake of fire, Rev 20:14, 15. There are two separate judgements, but only one resurrection as all will occur at the same time at the Great White Throne Judgement then will God renew the heaven and earth and usher down the New Jerusalem.
John 5:28 Marvel not at this: for the hour is coming, in the which all that are in the graves shall hear his voice, 29 And shall come forth; they that have done good, unto the resurrection of life; and they that have done evil, unto the resurrection of damnation.
John 6:40 And this is the will of him that sent me, that every one which seeth the Son, and believeth on him, may have everlasting life: and I will raise him up at the last day.
Rev 1:7 Behold, he cometh with clouds; and every eye shall see him, and they also which pierced him: and all kindreds of the earth shall wail because of him.
A 1000 years in Rev 20 is not literal years, but only symbolic of a certain period of time as nowhere else in scripture does it mention a literal 1000 year reign of Christ here on earth, but symbolic as in Deuteronomy 7:9; 1Chronicles 16:15; Psalms 50:10; 90:4; 105:8 Ecc 6:6; 7:28; Daniel 5:1; 2Peter 3:8.
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