It’s not a penalty. It’s a wage, and the wage is a metaphor. For example: “If you work hard, you’ll get the job done.” The payment for “working hard” is “getting the job done.” “Getting the job done” is a natural result of having worked hard. It is, metaphorically, your wage or your reward for having worked hard.
Death, likewise, is the natural result of having sinned (and continuing to sin, presumably.) If you jump into the water, you’ll get wet. Getting wet isn’t a penalty–it’s just what happens when you jump into the water. Death is just what happens when you sin.
To define death here, clearly we’re not talking primarily (or perhaps at all) about physical death. When we are (from our own perspective) cut off from God, who is the continual source of all kinds of life, we are dead. Even if we are biologically alive, with regard to God, we are dead (from our own pov). If you have rejected, for example, your father who committed some affront against you–or someone else you love, you might say, “He is dead to me.” He isn’t dead to anyone else, just to you. It is a relationship statement. The benefit of the relationship has been destroyed by what he did (or by how you perceived it) and you are essentially dead to one another–you by your own choice, and he by, again, your own choice. You are dead to him because the line of communication is broken–maybe he’s okay with that or maybe it breaks his heart, but if the two of you are separated by rejection from one or both parties, you are dead to one another.
GOD obviously continues to sustain with life all of his creatures who are biologically alive. If he ever withdrew that constant flow of life, we would all cease to ever have existed. Maybe (depending on your view of the state of the soul following physical death) God sustains ALL of His creatures (whether alive or dead to US) with that constant flow of life. Nevertheless, to many of His creatures, God is dead to them–or perhaps they have yet to rise to the level of consciousness that would enable them to realize His presence at all. Please notice this is a statement about CREATURES, not about GOD. God sustains you even if, from your point of view, He does not or should not exist. WE are separated from HIM by our own sin consciousness. It is always the CREATURE who is said to need to be reconciled to GOD. In the prodigal son, does the Good Father see his wayward boy as dead? Does HE refuse to have a relationship with the son? It is the son refusing the Father, needing to be reconciled to the Father. THAT is where we are–we are dwelling in death until we allow ourselves to be reconciled to our Father who waits with yearning love for us to be reconciled to HIM.
This is what happened (to my limited understanding and descriptive ability). Adam was the result of a long evolutionary process (maybe someone will one day change my mind about that, but that’s how I see it now). When Adam became biologically capable of sustaining self-aware consciousness, God breathed into him the breath of life. He became more than a biological machine, but rather a living soul. (I know that’s clunky and I am very aware of the problems with this view, but it’s my rough, rough sketch which I hope I will one day know how to refine or repair.) Adam had the choice to eat from one or the other tree–the one representing the LIFE that comes from God, the other representing the siren song of Adam’s own intellect. The intellect wasn’t and isn’t wrong, but the dependence on it IS wrong. It is like trusting in a damaged walking stick. The moment you try to vault yourself over a stream or other obstruction, it will break and in addition to dumping you in the water, possibly even go right through your hand. Our own knowledge is a good tool, but it is a horrible master. Why was Adam separated from the TOL after his poor choice regarding the other tree? I don’t know. Maybe so long as Adam ate from the Tree of Life, he lived? The moment he separated himself from it by choosing instead his own cleverness, he died to the TOL (which is most simply put, representative of God).
Had he continued to eat from the TOL while actually trusting in his own cleverness, what would he have become? I don’t know. If the TOL somehow kept him alive biologically, perhaps something awful. Like a Hitler (who did have a convoluted, insane system of cleverness) but worse, a Hitler who was physically deathless. Maybe Adam COULD have been deathless had God not withdrawn the TOL from him (metaphorically speaking). How horrible would that have been, in a man depending primarily on his own cleverness? It’s just speculation. Maybe all that the expulsion from the garden means is that in choosing the TOKOGE, Adam made the TOL inaccessible to himself. Eating from (choosing as his source) the TOKOGE, he could not simultaneously choose as his source, the TOL.
Primarily Adam represents Israel of course, but by extension he also represents all of mankind. WE, being Adam’s children, do not have the promise of never-ending biological life, never experiencing death. Our biology, dependent as it is on millennia of evolution requiring violence–the hunter gatherers would not have survived or developed without it–damns us to sinful behavior. I suppose that theoretically Adam could have taken that hand up out of the biological swamp and onto a higher plain of existence right then and there. God knew he would not, but it was a first step–an opening of the eyes.
Jesus came along to bring that choice back to us. We must die biologically at some point, yes. This body of death, Paul called it, that tempts us to sin with its instincts for survival at all costs and forwarding oneself that oneself and one’s offspring will be more likely to survive and thrive and pass on our all-important genetic code to new generations. All this while trampling the weak. Evolution, which served to develop us into creatures who could know God, now poses a barrier to our knowing God. We need to transcend it by taking the hand of Jesus and allowing Him to pull us up to the next level. But Paul also says that the biological death is not the end of our bodies.
He speaks of a seed (as did Jesus) that falls down into the earth and dies in the process of giving birth to the new plant. Is it the same body that rises as the body that died? Yes. No. Is that tall pine tree outside my window the same little pine nut that escaped being eaten by a squirrel who perhaps buried it years before I was born? Yes. No. It is the same. Everything necessary to tell the pine tree who it was and was to be was in that tiny nut–not even the size of a lentil. Not even half. Yet the pine tree identity was packed up inside, along with the life and enough nutrients to get it above the ground and putting out thread-like leaves to the sustaining sun. The only things the pine tree needs from there on out are a few nutrients from the soil (really very few for a pine tree), the sunlight and the rain. That’s it. So yes, it IS that tiny, tiny thing that started it. The tree came out of the nut and the tree is the nut. Only it isn’t. You have only to look at it to see that.
The death is necessary because we are children of Adam and Eve and can only ever be mere humans unless something happens to change that. Jesus died as the representative and the new head of the human race. IN HIM, we are One New Man. The old human race murdered him and put him into the ground with the rest of the dead ones. But Jesus rose from among the dead ones and made a way (yes, literally made a way) for them to follow in His victory parade. He beat the strong man (death or the devil or whatever you want to have that represent). He cracked the four-minute mile. Once an athlete did this, which took so many, many years, everyone started doing it. Do you remember? Are you old enough to remember? Only I don’t think anyone of us could have cracked the resurrection . . . we needed Christ for that. God raised Him from among the dead–He reversed the chaos that is death and did the undoable. He reversed the laws of thermodynamics and turned the whole human race (and through us the whole world) onto a new track into a life we never could have accessed without our champion pioneer, Jesus the Christ, breaking the trail for us. We follow in His power or not at all. Because we’re a bunch of exclusivist jerks? No. Because it’s the only way to life–not our fault–that’s the way to get to life and if you want to get to life, you just have to go that way. We regret any offense this may cause–but on the bright side, God guarantees (and delivers) ultimate satisfaction, and everyone will eventually take this deal voluntarily and with absolutely giddy joy.
There was SOMETHING Jesus needed to do, and ONLY Jesus COULD do. Yes, the dead (including us) really did need rescuing. From the devil? I dunno–I don’t think so. I mean, I do think there IS a devil, but it seems to me that the deliverance we needed was from the grave–from death and from the fear of death. In order to be delivered from death (which is the inevitable wage of sin), we need to become the sort of persons who not only despise and recoil from sin and sinning, but who are absolutely victorious over sin and sinning. Not even Mother Teresa could be that person–and she would absolutely insist that she (inasmuch as she succeeded) did NOT do it on her own. We are all in process of being changed into the image of God’s perfect Son. Some are farther on than others but no, nobody can do this on his own. Nobody.