This post is intended to answer the questions left by the last. In brief: how is it that the world is full of existent sinners that do not feel the wrath of God poured out on them? We are kept alive because God desires to work in us to our good, which is found in his glory. How then does God glorify himself in our good when we are sinful? By showing his power to make us righteous.
Christ came, in the incarnation, fully human and fully God. He came as a new representative. As our representative, representing us as only a human being can, he did choose to seek all of his joy in the Father, he dealt with the wrath of God, taking the righteous punishment for our sins, as only the infinite God is able to do in a finite period of time.
Yet this new representative, Jesus Christ, does not represent all of those who come after him, but only those who claim him. Where Adam represented us all because he was first, Jesus represents those who are made in him, who choose him. Yet we are all sinners, our wills are turned against God, we do not want to be in Christ, unless our eyes are opened to the fact that only in Christ can we find true joy. Our sin payed for, we may now see God, and our wills may be pointed to him, our desire may then become to seek our joy solely in the will of God.
Therefore, by accepting by faith the salvation that Christ has bought us, we are found in him. Being found in him we are being made like him, for, being in him, the Spirit of God is in us, and he is shaping us into the image of Christ, that we might desire the things of God. Also, being in him, we share in his righteousness, and therefore our sins are no longer counted against us. His atonement has payed for all our sins, regardless of when they are, were, or will be. Why should a God who exists beyond time be bothered that our sins were committed before we believed? As all of time is present to him, so all our sins. If all our sins are present, so also all our sins are payed for.
"For those whom he foreknew he also predestined to be conformed to the
image of his Son, in order that he might be the firstborn among many
those whom he predestined he also called, and those whom he called he
also justified, and those whom he justified he also glorified." (Romans 8:29-30) So we are justified by faith in Christ's work on the cross, and also glorified. As God is beyond time, he may say that our glorification has already happened, and as he is beyond time, he is accomplishing it now, in sanctification. Justification is, in a sense, the beginning of our lives in Christ, and glorification the end. So those who begin in Christ will also end in him.
Which is greater: the craftsman who can make a thing, but cannot then fix it if it breaks, or the craftsman who, having made an intricate device, when it breaks, is able to fix it? And which is better: the father who rejects his child when he goes against his will, or the father who loves the child enough to bring him back into the family, and is patient to teach that child what his will is?
So we who were in the wretched state of sin are now made new by our father, the master craftsman, and he will by all means keeps us, Christ will not lose any of those given him by the Father. Where before we were lost and acting according to our own desires, now we are found, and, by the power of God working in us, our wills are being made new that they might seek the will of God, which is our hope. Where before we had no desire to seek that which would bring us most joy, now we are found in him who brings us all joy, to the glory of God.