Doesn’t 1 Thess.4:17 mean that at Christ’s second coming, the flesh from the grave of those who are dead, is rejoined with the spirit?

On the difference between our flesh body, and that glorious body, and dimension of Heaven…

I John 3:2
2   Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when He shall appear, we shall be like Him; for we shall see Him as He is. (KJV)

     The Apostle John states that though those who accept Christ as Savior, and are now known as ‘sons of God’, we STILL don’t know for sure ‘what we shall be’, but… we know ‘we shall be like Him’ (having a similar body as Christ’s Glorious resurrected Body). If John knew clearly that ‘spiritual body’ which Paul named in I Cor.15:44 was of the ‘flesh’ order, then wouldn’t he have said so? Well, then of what order was Christ’s Glorious Body after His resurrection?

John 20:19-20
19   Then the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled for fear of the Jews, came Jesus and stood in the midst, and saith unto them, “Peace be unto you.”
20   And when He had so said, He shewed unto them His hands and His side. Then were the disciples glad, when they saw the Lord.

     What type of Body is talked about in these verses? Even though Christ’s Glorious Body has the marks of His crucifixion, can flesh walk through walls or doors? One who still chooses to believe that spiritual body is flesh, still must explain ‘how’ it can go through dimensions like Christ’s did here, appearing ‘midst’ His disciples without entering the room the way flesh must enter. One may call it flesh if they want, but clearly, it is not the same type of flesh body we all have right now living on this earth. Christ knew they would have a difficult time understanding these things also, so He even ate man’s food in His resurrected Body, to show them It is able to live and function on earth similar to flesh. Weren’t these examples from our Lord for us today also?:

Luke 24:40-43
40   And when He had thus spoken, He shewed them His hands and His feet.
41   And while they yet believed not for joy, and wondered, He said unto them, “Have ye here any meat?”
42   And they gave Him a piece of a broiled fish, and of an honeycomb.
43   And He took it, and did eat before them.

     Christ’s Message here about the resurrection body is of ‘strong meat’ (Heb.5). His disciples are to understand it; thus He went to whatever length necessary by example, to make sure they understood. What did the Israelites in the wilderness eat for forty years? Heavenly manna, known as angel’s food. Wow! Man’s flesh can also eat angel’s food, angels can eat earthly food; the bodies must be similar, but of a different order. None have gone to Heaven in the flesh and lived without being transfigured (such as Elijah and Enoch). This is why Isaiah got so scared when he was given a vision. He thought he had died (Isa.6). God’s chosen may be given ‘visions’ of Heaven, as John was given, but to actually ‘be’ there, one must leave this flesh. Even the below example from Paul shows how the ‘spiritual body’ is what was ‘caught up into Paradise’, not the flesh:

2 Cor 12:2-5
2   I knew a man in Christ above fourteen years ago, (whether in the body, I cannot tell; or whether out of the body, I cannot tell: God knoweth😉 such an one caught up to the third heaven.
3   And I knew such a man, (whether in the body, or out of the body, I cannot tell: God knoweth;)
4   How that he was caught up into paradise, and heard unspeakable words, which it is not lawful for a man to utter.
5   Of such an one will I glory: yet of myself I will not glory, but in mine infirmities. (KJV)

     That ‘man’ was probably Paul, even as he was stoned once and left for dead (Acts 14:19-20). Might this event Paul is speaking about here have anything to do with a ‘near death experience’? Sure does, as he even stated he didn’t know whether he was in the body (flesh body), or out of the body. This has nothing to do with how the New Age groups teach how to have ‘out of body’ experiences. I personally know at least two Christians who were involved in accidents, and experienced this near death event, and have heard their testimony of angels speaking to them.
Did you notice the term ‘caught up’? Might this have something to do with ‘how’ those alive in the flesh when Christ returns are ‘changed’ to their ‘spiritual body’? Again, yes. Isn’t this phrase ‘caught up’ even used there in I Thess. 4:17? Both occurrences of ‘caught up’ is the Greek word ‘harpazo’, meaning ‘to carry off by force’. I Thess.4:17 is the same event which Paul experienced being ‘caught up’ to the ‘third heaven’ age, the Holy City which exists right now, in that spiritual dimension, where Heaven is. The DIFFERENCE being, Paul did not die, and thus his spiritual body returned back into his flesh body; the ‘silver cord’, which attaches our ‘spiritual body’ to the flesh, was not ‘loosed’ (Eccl. 12:6). At I Thess.4:17, when Christ returns, everyone alive in the flesh, will have their ‘silver cord’ loosed from the flesh body. The spiritual dimension will be fully revealed, and it will be most wonderful.
Note that Paul said he was ‘caught up’ into Paradise? The Greek Septuagint Bible, which is older than our KJV, renders the word ‘Eden’ as ‘Paradise’. Also, remember what Christ said to the malefactor crucified with our Lord, who believed on Him.

Luke 23:43
43   And Jesus said unto him, Verily I say unto thee, “To day shalt thou be with Me in Paradise.”

     When would that malefactor be with Jesus in Paradise? “To day”, meaning as soon they got done with their old flesh bodies dying on the cross, giving up the spirit trapped in those flesh bodies (ghost; also see Eccl. 12). Those ‘in Christ’ who die TODAY, put off this flesh body also, the ‘silver cord’ being loosed from the flesh, and they go into Paradise, where Christ and our Father are, along with His saints. Those not ‘in Christ’ go to a different place, but still in Heaven, a place of separation.

Luke 16:22
22   And it came to pass, that the beggar died, and was carried by the angels into Abraham’s bosom: the rich man also died, and was buried;

     Both, Lazarus, and the ‘rich man’ died, and their flesh bodies were buried. That’s the meaning of ‘also’ died, and was buried. The ‘angels’ carried Lazarus to one side in Heaven, where Abraham is, but the ‘rich man’ was carried to the ‘pit’, where Satan and his are. This is not a ‘parable’, or an analogy Christ is teaching within these verses. It is an ‘explanation’ for that Heavenly state, even now as I write this.

Luke 16:23-26
23   And in hell he lift up his eyes, being in torments, and seeth Abraham afar off, and Lazarus in his bosom.
24   And he cried and said, “Father Abraham, have mercy on me, and send Lazarus, that he may dip the tip of his finger in water, and cool my tongue; for I am tormented in this flame.”
25   But Abraham said, “Son, remember that thou in thy lifetime receivedst thy good things, and likewise Lazarus evil things: but now he is comforted, and thou art tormented.
26   And beside all this, between us and you there is a great gulf fixed: so that they which would pass from hence to you cannot; neither can they pass to us, that would come from thence.

1 Cor 15:50
50   Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; neither doth corruption inherit incorruption.

     Paul stated this about our ‘flesh and blood’ in a manner which is ‘solid’ Truth. He didn’t leave any maybes, or we don’t really know in-roads to add. It’s important as Christians, to realize who the ‘author’ is, of the doctrine of wanting to keep these old flesh bodies forever. That includes the false doctrine that the dead flesh body is somehow put back together with the spirit when Christ returns. (Christ’s miracles of raising the dead was for His Mission as Savior). Of what order are those who push the following false idea today, that through mapping genetics, man can cure ‘all’ flesh disease, and thus bring ‘immortality’ of the flesh? That type of flesh order thinking is from Satan, not our Father and His Son Christ Jesus. And Satan wishes to keep your thinking in the flesh, a ‘carnal mind’, and not in the spiritual Mind of Christ (1 Cor.2:16; 1 Pet.4:1; Rom.8).