Paul teaches in I Corinthians 15 that those covenant- keepers who have not experienced what John would have called the first death, and who are therefore still burdened by sin and its curse, will join those covenant- keepers who return with Christ. For this to take place, they must be delivered from original sin and its curse, death. This will take place prior to their ascent into the sky. "In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed" (v. 52). This has to take place before the ascent because corruption cannot inherit incorruption. "For this corruptible must put on incorruption, and this mortal must put on immortality" (v. 53). This is Paul's theme of inheritance in this chapter. Eschatology has to do with point five of the biblical covenant model: inheritance. Paul is speaking here of the nature of the covenant-keeper's inheritance on judgment day. He will inherit incorruption. Whether he will subsequently receive rewards of gold, silver, and precious stones depends on God's retroactive judgment of his work, but he will inherit incorruption, which begins with the transformation of his death-cursed physical body and his sin-ravaged soul.
And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit. Howbeit that was not first which is spiritual, but that which is natural; and afterward that which is spiritual. The first man is of the earth, earthy: the second man is the Lord from heaven. As is the earthy, such are they also that are earthy: and as is the heavenly, such are they also that are heavenly. And as we have borne the image of the earthy, we shall also bear the image of the heavenly. Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; neither doth corruption inherit incorruption. Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. For this corruptible must put on incorruption, and this mortal must put on immortality. So when this corruptible shall have put on incorruption, and this mortal shall have put on immortality, then shall be brought to pass the saying that is written, Death is swallowed up in victory. O death, where is thy sting? O grave, where is thy victory? (vv. 45-55).The theological issue here is the separate physical condition of what the English-language version of the Apostles' Creed calls the quick and the dead. Covenant- keepers are spiritually alive in history. Jesus said, "Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life" (John 5:24). But there is a difference between the celestial body, which covenant-keepers inherit at the time of their physical death, and the earthly body, which they must occupy in history. This difference cannot be bridged by sinful men, not even at the last trump. They must receive their celestial bodies before they can be joined with covenant-keepers who have already received their celestial bodies. The dead in Christ will rise first (I Thes. 4:16). All flesh is not the same flesh, and the two cannot mingle together.
There can be and has been mingling in history between men and sin-free angels, but angels are not members of the church. They are not part of the bride of Christ (body of Christ), which the church is. There was also mingling between incorruption and corruption in the earthly ministry of Jesus Christ, but He was born of a woman by the Holy Spirit. He was God as well as a perfect man. God can mingle with sinful men.But God giveth it a body as it hath pleased him, and to every seed his own body. All flesh is not the same flesh: but there is one kind of flesh of men, another flesh of beasts, another of fishes, and another of birds. There are also celestial bodies, and bodies terrestrial: but the glory of the celestial is one, and the glory of the terrestrial is another. There is one glory of the sun, and another glory of the moon, and another glory of the stars: for one star differeth from another star in glory. So also is the resurrection of the dead. It is sown in corruption; it is raised in incorruption: It is sown in dishonour; it is raised in glory: it is sown in weakness; it is raised in power: It is sown a natural body; it is raised a spiritual body. There is a natural body, and there is a spiritual body. And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit. Howbeit that was not first which is spiritual, but that which is natural; and afterward that which is spiritual. The first man is of the earth, earthy: the second man is the Lord from heaven. As is the earthy, such are they also that are earthy: and as is the heavenly, such are they also that are heavenly. And as we have borne the image of the earthy, we shall also bear the image of the heavenly. Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; neither doth corruption inherit incorruption (vv. 38-50).
The only biblical example of mingling in history between sinful humans and a deceased saint is Samuel's appearance to Saul and the witch of Endor. Calling him up from the grave was a major sin on the part of Saul, and he lost his kingdom and his life the next day because of it. Samuel told him: "Moreover the LORD will also deliver Israel with thee into the hand of the Philistines: and to morrow shalt thou and thy sons be with me: the LORD also shall deliver the host of Israel into the hand of the Philistines" (I Sam. 28:19). The judgment on Saul was an extension of his sin. Saul and his sons would soon mingle with the dead. His family's kingly inheritance in Israel would end.