Of the Abrogation of the Covenant of Works
“And that covenant [of works] is so really abrogated, that it can on no account be renewed. For, should we imagine God saying to man, “If, for the future, thou canst perfectly keep my law, thou shalt thereby acquire a right to eternal life,” God would not by such words renew this very covenant of works; for sin is now pre-supposed to exist, which is contrary to that perfection of obedience which the covenant of works requires. God would therefore transact here with man on a different condition, whereby, forgiving the former sin, he would prescribe a condition of an obedience less perfect than that which he stipulated by the covenant of works; which, excluding all sin, knew nothing of forgiveness of sin. Nay, such a transaction would be so far from a renewal of the covenant of works, that it would rather manifestly destroy it; for the penal sanction makes a part of that covenant, whereby God threatened the sinner with death: so that, if he forgave him without a due satisfaction, he would act contrary to the covenant and his own truth.” Herman Witsius, “Economy of the Covenants. Volume 1 p. 199
Google Books Witsius Economy
It appears Robert Shaw agrees with Witsius.
As Robert Shaw states, Adam was created under this Law in a natural form but then was brought under it in the form of a Covenant.
Section I.–God gave to Adam a law, as a covenant of works, by which he bound him and all his posterity to personal, entire, exact, and perpetual obedience; promised life upon the fulfilling, and threatened death upon the breach of it; and endued him with power and ability to keep it.
The law, as thus inscribed on the heart of the first man, is often styled the law of creation, because it was the will of the sovereign Creator, revealed to the reasonable creature, by impressing it upon his mind and heart at his creation. It is also called the moral law, because it was a revelation of the will of God, as his moral governor, and was the standard and rule of man’s moral actions. Adam was originally placed under this law in its natural form, as merely directing and obliging him to perfect obedience. He was brought under it in a covenant form, when an express threatening of death, and a gracious promise of life, was annexed to it; and then a positive precept was added, enjoining him not to eat of the fruit of the tree of knowledge, as the test of his obedience to the whole law.–Gen. ii. 16, 17. That this covenant was made with the first man, not as a single person, but as the federal representative of all his natural posterity, has been formerly shown. The law, as invested with a covenant form, is called, by the Apostle Paul, “The law of works” (Rom. iii. 27); that is, the law as a covenant of works. In this form, the law is to be viewed as not only prescribing duty, but as promising life as the reward of obedience, and denouncing death as the punishment of transgression. ….
Section II.–This law, after his fall, continued to be a perfect rule of righteousness; and, as such, was delivered by God upon mount Sinai in ten commandments, and written in two tables; the first four commandments containing our duty toward God, and the other six our duty to man.
Upon the fall of man, the law, considered as a covenant of works, was annulled and set aside; but, considered as moral, it continued to be a perfect rule of righteousness. That fair copy of the law which had been inscribed on the heart of the first man in his creation, was, by the fall, greatly defaced, although not totally obliterated. Some faint impressions of it still remain on the minds of all reasonable creatures. Its general principles, such as, that God is to be worshipped, that parents ought to be honoured, that we should do to others what we would reasonably wish that they should do to us–such general principles as these are still, in some degree, engraved on the minds of all men. – Rom. ii. 14,15. But the original edition of the law being greatly obliterated, God was graciously pleased to give a new and complete copy of it. He delivered it to the Israelites from Mount Sinai, with awful solemnity. In this promulgation of the law, he summed it up in ten commandments; and, therefore, it is commonly styled the Law of the Ten Commandments.