not every law written in the Old Testament is a part of this Natural Law.
This is a good point.
However, sin(s) result in death is not only about spiritual death (although this is the main point) but also natural death, such as sickness, restlesness, depression, chaos, and also-- yes I agree that this is the main point-- the ultimate eternal death as in the spiritual meaning.
The good news is that if we can overcome these sins, then we can attain eternal life with God. The even better news is that when we overcome these sins, we will literally be in Heaven on Earth.
The good news is not good enough if we focus on “ourselves” overcoming sins to attain God.
If we can overcome sins, surely we will go to heaven. But that is not “The Good News” yet (other religions teach this too). The Good News is what makes the difference between The Old testament and The New, and at the same time explain why the OT then and NT now.
We overcoming sins is the teaching of the law (the old testament). This way of thinking is perfected (in the new testament) when God proclaim that sin (singular, the source of sins-plural) is overcome by faith in God’s will (and God’s will is to save not to punish).
In the old testament God try to explain to us what “to sin” mean. By using “defiled food”, God taught us that sin is like “dirty/defiled food”, it causes sickness and ultimately death. If anything touch anything “defiled” would be defiled as well. Sins spread through contact is like defiled food and sick people spread desease. For example: gay people spread their desease through contact with others. So bad behavior from bad social contacts. Children learn bad things from hearing and seeing them (bad contacts). Bad things feed our anger (bad food) and we take them so we become more angry. To overcome this, the old testament teach us to stay away from anything defiled, through the law.
In the new testament, God then teach us how to be clean living in this defiled earth : by touching God. To be defiled is not from outward cause but inward (the world cannot defile us, but we can defile ourselves). Inward sin causes outward sins. Inward holiness couses holy actions. Outward holiness does not produce inward holiness but the otherway round does. In this way, the wold cannot defile us because God’s will is stronger than human’s: “not by our might but by the spirit of God.” The spirit of God is in us.
God’s spirit is explained here and there in the old testament (such as in Isiah, the above quote) but never really definitively clear until Jesus came.
Having said this, I think your letter make some pretty good points especially about the bible is not to be taken as historical, but spiritual/ theological, although historical truths present in them. The spiritual part (out of the historical part) of the bible then have to explain God’s spirit as the focus of The Good News in the new way of thinking in the new testament : again, “not by might but by God’s spirit”. Not what I do (outward action of holiness) but by believing in what God does for me (inward holiness). In this way the teaching of the Old testament is perfected (fulfilled) in our life. That we become holy (the doer of the law) but not by mere human effort to observe the law, but by trusting in God (who is love and mercy).
By the way, I do not claim to speak for God. This letter was written by a very fallible, sinful human who is more concerned with his own sin than with the sin of others.
We don’t speak for God, but God speak through us if we believe Him. He put His spirit upon us so that we speak His truth and-- ultimately, live His truth as well.
God bless you.