Why was Kline so concerned to recognize that works was the controlling administrative principle of the Mosaic covenant? There are at least five reasons.
The first reason is that Kline perceived that if one denies the works principle in the Mosaic law, then one will view the blessings and curses of the Mosaic covenant as part of the administration of grace and promise, a mere administrative continuation of the Abrahamic covenant. Doing this will distort one’s understanding of the covenant of grace. If the conditionality of the Mosaic covenant (do this and live; blessing for obedience; curse for disobedience) is actually part of the covenant of grace, then that conditionality will change the role of good works or evangelical obedience in the covenant of grace. Good works will necessarily play more than an evidentiary role and become a condition for receiving the blessings of the covenant of grace. Making good works a condition of receiving the blessings of the covenant of grace is in conflict with the purity of Paul’s doctrine of justification by faith alone.
The rejection of the works principle in the Mosaic law leads logically to interpreting the blessings and curses of the law as God’s way of dealing with his redeemed people in every epoch of the covenant of grace, not just in the old covenant, but also in the new.
“As he develops the thesis that God’s covenants are characterized by a continuum of governmental principle rather than by a works-grace contrast Shepherd affirms the unity of all these covenants, preredemptive and redemptive, specifically proposing that they all have in common both demand and promise” (“Of Works and Grace,” 88).
“This tendency is displayed in the more immediate sphere of Murray’s influence. In the teaching of his successor, Norman Shepherd, preredemptive and redemptive covenants were flattened into a continuum of promise and demand” (“Gospel until the Law,” 435 and n9).
Here are some quotes from theologians whose denial of the Mosaic works principle leads them to such a continuum of promise and demand:
“The Mosaic covenant in respect of the condition of obedience is not in a different category from the Abrahamic. It is too frequently assumed that the conditions prescribed in connection with the Mosaic covenant place the Mosaic dispensation in a totally different category as respects grace, on the one hand, and demand or obligation, on the other. In reality there is nothing that is principally different in the necessity of keeping the covenant and of obedience to God’s voice, which proceeds from the Mosaic covenant, from that which is involved in the keeping required in the Abrahamic” (John Murray, “The Covenant of Grace,” 22).
“In the Mosaic covenant, the Lord did not establish a covenant of works with his people. He did not establish a covenant on the basis of a principle that is the very opposite of that on which the Abrahamic covenant is founded .... Like the Abrahamic covenant, the Mosaic covenant has two parts, promise and obligation. In the Abrahamic covenant, the focus is on promise. In the Mosaic covenant, the focus is on obligation – but promise does not receded into the background .... The obedience required of Israel is not the obedience of merit, but the obedience of faith. It is the fullness of faith. Obedience is simply faithfulness to the Lord .... The Abrahamic and Mosaic covenants do not exhibit opposing principles of grace and merit, or of faith and works. In both covenants there are promises, and these promises are received by a living and active faith. In both covenants, there are warnings about the consequences of unbelief and disobedience .... The penalties threatened for disobedience in the Mosaic covenant are fully in line with this provision of the Abrahamic covenant. Threatened curses for disobedience do not transform either the Abrahamic covenant or the Mosaic covenant into a covenant of works” (Norman Shepherd, The Call of Grace, 38-40).
This has very practical implications for preaching. How should the blessing and curse passages in the Old Testament be preached to the new covenant people of God? Do we tell them, as Shepherd would, that they must be obedient to God and if they are not, they will be cursed? I would hope not. To preach that way would be to bring the new covenant people of God back under the bondage of the law that we have been delivered from in Christ. Paul says we are free from the curse of the law. He says that we have died to the law, and are no longer under its bondage and fear. We serve God in the new way of the Spirit, not in the old way of the letter.
“The irony of all this is that a position that asserts a continuum of ‘grace’ everywhere ends up with no genuine gospel grace anywhere. An approach that starts out by claiming that a works principle operates nowhere ends up with a kind of works principle everywhere. What this amounts to is a retreat from the Reformation and a return to Rome” (“Covenant Theology Under Attack”).