While I agree with some of what Hart says regarding the need of liberation from the power of sin and death as opposed to the assuaging of the inherited guilt of “original sin,” I don’t buy all of it.
Paul is making the point in Romans 5:12 onward that sin was in the world before Moses and the Law/Torah. The proof is that all died. This is in line with the Genesis narrative, Adam’s sin brought death, not the other way around. It is also in line with later OT thought, the soul that sins will die, not the soul that dies will sin.
Strands of first century Jewish thinking was that the Law, and observance of the Law, was the antidote to universal sin and death, and would bring eschatological life. Paul’s main point is not how sin and death came to all, he assumes that. It is that the Law/Torah, and observance of its written code, no matter how stringent, provides no advantage and no solution to the problem, and could never give life.
This is why he had already said in 4:15 that, “…The Law brings wrath, and where there is no Law, there is no transgression.” He does not say there is no sin without law, as you have rendered it, a hopeless contradiction with Chapter 5, where he said that sin was already in the world before the Law. Paul was saying that all the Law could do was turn sin into transgression, the crossing of an explicit boundary or norm.
To use a rough illustration, if we drive 85mph down a neighborhood street with no posted speed limit, we instinctively know that we are doing something wrong, we are missing the mark of safe driving, and we know that it is not safe for us or anyone else. We might even see people get hurt and killed, reinforcing that knowledge. But, if we see a sign that says 30mph speed limit, that turns our speeding into transgression of a known law or community norm. This was Paul’s point about the Law. Without it, there was no explicit transgression. With it, sin became transgression. Iow, the Law, in opposition to Jewish belief, could not serve as an antidote to sin, it made the whole situation more dire, shutting people up under its explicit pronouncement and penalty. The promises of righteousness and life that were attached to Torah observance were a mirage in Paul’s thinking. Only God could bring such through his messiah and the Spirit.
Paul’s reference to Adam vis a vis Paul’s picture of sin and death, is that Adam’s sin unleashed a power that enveloped all people, (which Hart seems to say) even over those who did not sin in the manner Adam did by violating a known command. The dominance of that power could be seen in that all humans sinned between Adam and Moses (living a distortion of true humanity and missing its mark like the speeding driver)…the evidence being that all died. The introduction of the Torah at Sinai did nothing to solve the situation. It actually increased sin’s stranglehold, turning sin into transgression, and reinforcing the result…death. Jews with the Law had no advantage regarding this, over Gentiles without it.
1 Cor 15 is making a similar point…death unleashes its venom through the sting of sin, and what energizes sin is…the Law! This is a vortex from which there is only one escape…“Thanks be to God who gives us the victory (over these combined and aligned powers) through our Lord Jesus, the messiah!”