Well, let's cut to the chase-- in ancient adoptions (specifically the adoption was the Roman empire) when a rich couple adopted another child as their heir, even though the original parents were still living the child was considered be part of the household of the adopted parents, and enjoyed many of the prerogatives of that household. They were no longer subject to their old parents but to their new parents. Yet, their old parents still had influence on their biological child. However, at the moment of the finalization of the adoption by the adopted father, the children became full children off their adopted father and any influence and any legal ties that they had to their biological parents were completely and irrevocably broken. From that point on the original parents had no claim whatsoever on the child.
This is what happens with us. When we are saved we are adopted by God. The Bible makes it clear that He chose to adopt us (Ephesians 1:4-6). At this time in our lives, even though our earthly environment, namely the dominion of the prince of the power of the air, still exists, we are considered part of God's family. You may have been born in sin but you are now the child of God. But we are still affected by our old environment, by our old parentage, if you like. But the day that we are raptured or taken to heaven, at that moment God completes the adoption legally and at that point our original environment (sin parentage) no longer has any claim on us whatsoever, legal or otherwise. We are 100%, completely, totally free from our earthly bonds!
To put it in terms of our salvation-- scripture is clear that our salvation is both past, present, and future. Right now you and I have been saved from the penalty of sin: in other words our sin is no longer held against us and we're secure for eternity. But at this moment in our lives we are being saved from the power of sin: this is the process of our sanctification. But in the future, at the very moment when we enter heaven, we shall be saved from the very presence of sin.
In the same way, when our adoption is complete, Satan will no longer have any hold whatsoever on us; in fact he will no longer exist in our lives. Glory to God! We shall no longer know what sin is at all, and we will no longer have even the slightest pull toward this old life. Glory to God! We will fully be the children of God, in full possession of our inheritance, and be just like Him ... perfect images of our Father! Glory to God!
And that respectfully, is the end of the story. So I repeat yet again-- Glory to God!
And that is exactly what I have posted. As you wrote...
"But the day that we are raptured or taken to heaven, at that moment God completes the adoption legally and at that point our original environment (sin parentage) no longer has any claim on us whatsoever, legal or otherwise. We are 100%, completely, totally free from our earthly bonds!"
In the same way, when our adoption is complete, Satan will no longer have any hold whatsoever on us; in fact he will no longer exist in our lives. Glory to God! "
So we agree that our adoption is completed before the world began, is by faith completed now yet is in a state of hope and the full acquisition of our adoption and inheritance is yet to come.
It is especially important that Satan will no longer have any hold on us and not only not exist in our lives but he won;t exist in heaven either.
This is critically important for the pre-trib rapture because it is not Jesus who completes our adoption for He is our brother. Jesus brings us to the Father to complete our adoption and this is the reason the Father sent Jesus to redeem us.
If we understand what hope is, that we cannot hope for what we have in full, and that we must appear before the Father for the completion of our adoption, then the post-trib doctrine is in denial of the need to appear in heaven before the Father to complete our adoption.
For simplicity, I like how this theologian puts it regarding our adoption papers as God's guarantee...
15 For you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, “Abba! Father!” 16 The Spirit himself bears witness with our spirit that we are children of God, 17 and if children, then heirs—heirs of God and fellow heirs with Christ, provided we suffer with him in order that we may also be glorified with him. (Romans 8:15-17, ESV)
This gives us certainty that we have been adopted as sons, but then there's a clarification a few verses later:
And not only the creation, but we ourselves, who have the firstfruits of the Spirit, groan inwardly as we wait eagerly for adoption as sons, the redemption of our bodies. (Romans 8:23, ESV)
So we see that we are still waiting for adoption! We are at once adopted and waiting for adoption. In a sense, our adoption papers have been signed, we've been given a new family, but we're still in the orphanage. Though we have a future which we eagerly await, we have a present life which is filled with purpose and hope because of the firstfruits of the Spirit, the promise of things to come.