Sanctification and the Third Use of the Law: Considerations...

For consideration regarding sanctification:  For those who put such priority on the 3rd use of the law as a strict obedience to the Mosaic Law, i.e. the Ten Commandments, how to explain the fact that between Adam and Moses there was no written law(!) affixed with blessings, threats, and curses, in the form of the Mosaic covenant? - Rom 5:13 "for sin indeed was in the world before the law was given, but sin is not counted where there is no law. 14 Yet death reigned from Adam to Moses..." There was clearly expressed covenantal law given to Adam ("thou shalt not eat...") and also given to Israel through Moses. But none given in the period between the two.  The law covenant of Adam ended when he disobeyed and ate the forbidden fruit. That covenant of law didn't extend into the patriarchal period. Also, Paul writes in verse 13 that sin was not counted [not imputed] in the period before the Mosaic law covenant was given to Israel. So, no accounting of sin in the absence of a covenant of law?... interesting. In addition, Abraham had no Written Law as a rule of obedience by which to live a godly life. There's little to support that he was all about keeping "God's laws" per se (gives Sarah as his "sister" to Abimelech!). Certainly Abraham was obedient to God ("By faith Abraham obeyed..." Heb 11: 8a), yet his obedience was done without aid of the Written Law.

And note that Abraham is called by Paul, the "father of us all." The emphasis in that title is on what Abraham received through faith - righteousness - because he believed God's promise, not on what he did in works of obedience: "That is why it depends on faith, in order that the promise may rest on grace and be guaranteed to all his offspring—not only to the adherent of the law but also to the one who shares the faith of Abraham, who is the father of us all, as it is written, “I have made you the father of many nations”—in the presence of the God in whom he believed, who gives life to the dead and calls into existence the things that do not exist" (Rom 4:16-17). 

Is this to say that we don't need the Ten Commandments or need not attend to the Law as the rule of righteousness and obedience informing us of the will of God? Not at all. The written law is a great help to better inform us as to God's holiness and our obedience as those created in the moral image of God. But I think the above does speak to the priority and ground of justification - the righteousness that comes through faith - when considering what empowers our obedience in sanctification; as well as the gospel truth that the moral law has been written afresh on the new heart and will of the justified sinner.

But this is the covenant that I will make with the house of Israel after those days, saith Jehovah: I will put my law in their inward parts, and in their heart will I write it; and I will be their God, and they shall be my people (Jer. 31: 33).   

For I delight in the law of God after the inward man (Rom 7: 22).