David, I am not sure this will help but I posted this a long time ago on my blog. It is a partial of the blog post.
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A statement was also made how the Mosaic should be viewed as an administration of death. I actually believe the above helps us answer this problem but I also saw this. We as fallen people tend to want to turn the Covenant of Grace into a Covenant of Works. Many people even do this concerning the New Covenant today when they add works to the equation of justification by faith.
In light of the passage mentioned in 2 Corinthians 3, which calls the Old an administration of Death, one must also read the prior passages to understand what context St. Paul is referring to the Mosaic Covenant in.
(2Co 2:14) Now thanks be unto God, which always causeth us to triumph in Christ, and maketh manifest the savour of his knowledge by us in every place.
(2Co 2:15) For we are unto God a sweet savour of Christ, in them that are saved, and in them that perish:
(2Co 2:16)
To the one we are the savour of death unto death; and to the other the savour of life unto life. And who is sufficient for these things?
(2Co 2:17)
For we are not as many, which corrupt the word of God: but as of sincerity, but as of God, in the sight of God speak we in Christ.
Christ and the Gospel were Preached in Moses and the Old Testament. In fact Jesus said as much as did the author of Hebrews.
(Luk 24:27) And beginning at Moses and all the prophets, he expounded unto them in all the scriptures the things concerning himself.
(Joh 5:46) For had ye believed Moses, ye would have believed me: for he wrote of me.
(Joh 5:47) But if ye believe not his writings, how shall ye believe my words?
(Heb 4:2)
For unto us was the gospel preached, as well as unto them: but the word preached did not profit them, not being mixed with faith in them that heard it.
(Heb 4:3)
For we which have believed do enter into rest, as he said, As I have sworn in my wrath, if they shall enter into my rest: although the works were finished from the foundation of the world.
The Mosaic was an administration of death the same way the New Covenant is to those who seek to turn the New Covenant into a Covenant of Works. We are so inclined to stumble because we will not believe Moses or Christ. We naturally tend to corrupt the Word of God and the Covenant of Grace by wanting to add our works into our justification before God. In doing so we are refusing the Cornerstone and Saviour. We become like those that Paul is speaking about, “to one they [Paul and the Apostles] are a savour of death unto death.” And how is to be considered that Paul and the Church is a savour unto death? They are because they do what Paul says he doesn’t do in the proceeding verse, “For we are not as those who corrupt the Word of God.” Those who corrupt the word are rejecting the Chief Cornerstone and depending upon their works or acts that contribute to their justification. The book of Galatians, Romans, and Hebrews have warnings and correctives for those who corrupt the word. But when they reject the truth they fall deeper into death. Even St. Paul acknowledged that the Law didn’t kill him. He was already dead and discovered it.
Rom 7:13 Did that which is good, then, bring death to me? By no means! It was sin, producing death in me through what is good, in order that sin might be shown to be sin, and through the commandment might become sinful beyond measure.
On another note I would mention that some say that the Mosaic was a Covenant that administered the Covenant of Grace as well as the Covenant of Works. Some differentiate that works was required in order for the Israelite’s to stay in and be blessed in the Land. They stayed in the Land based upon their works. Some say that this is different from the New Covenant. I am not seeing this difference. There are conditions set for us to remain in the Church even. For one thing Jesus himself said in Revelation 2 that he would remove a local Church’s candlestick if they didn’t repent. In 1 Corinthians 5 a man who was found to be exceedingly sinful was to be delivered to Satan and excommunicated from the Church. In Galatians 6:7 we are told that we reap what we sow.
I actually see what happened to the Church in the Old Covenant to be very gracious and just a form of discipline. It was grace that chastisement happened. It was grace that brought Israel back into the Land. They were the Church that was redeemed from bondage. God called them His people. They grew from dwelling in the wilderness to possessing the land. If it was by works then they would have never been brought back as they were. It looks quite the same to me as the man in 1 Corinthians 5. A casting out was performed. Excommunication was evident. Restoration by God’s grace was confirmed. The substance of both the Old pedagogical Covenant and the New are essentially the same. Salvation, regeneration, faith, repentance, justification, and sanctification for the Church is the same between both the old and new. It is all by God’s Covenant of Grace. The substance seems to be the same to me....
https://rpcnacovenanter.wordpress.com/2012/09/14/the-mosaic-covenant-same-in-substance-as-the-new/