First of all, here Calvin is specifically discussing the value in the Law as to how it functions. It has the same value now as when it was given through Moses to the Israelites. What he is not discussing is the sum total of how we grow in grace. The Mosaic Law still does the same thing as it always did---it reveals the righteousness of God and shows us what mankind is in relation to God's righteousness.
So when someone comes along and says that what Calvin says in his statement is unbiblical because because there are more efficient and effective ways of growing in grace, they ignore what is being said and read into it something which it is not even discussing. It also tends to divorce the two testaments from one another.
Well the first bolded statement is a huge problem that apparently you don't perceive at all. How did the Mosiac Law Covenant work out for Israel!? How many times did Israel come into severe judgment because they broke God's law covenant? In fact, do you know that God told Israel that they were more wicked than the surrounding nations -- pagan nations that did not have the Mosaic written code!?
But the second bolded statement is now getting very close to the crux of the problem with Covenant Theology! The "two testaments" are all but divorced! There is far more discontinuity between the Old and New Covenants than there is continuity. In fact, I came up with about 68 contrasts between the Old and New Covenants several years ago. And I challenge anyone to come up with that kind of number in terms of favorable comparisons! You should take Jer 31:31-32 to heart along with what Jesus taught about the two covenants (Mat 9:17; Mk 2:22; Lk 5:37). The Old and New Covenants are very different! So different that they differ in kind! It's no wonder at all that this warning from Jesus appears in all the Synoptic Gospels. Pouring new wine into old wineskins can only produce disastrous results.
I'll tell ya what: If you believe there is far more continuity between the OC and NC than there is discontinuity, why don't make a list of all those positive comparisons for us and post it here? Then afterwards, I'll post my long list of contrasts.
The Law most certainly curbed the actions of those to whom it was given, because without it they would not even know what the righteousness of God is. And if it had not been given, neither would we. That would be the knowledge of sin in Rom 7, the power of sin in 1 Cor 15, and the abounding of sin in Rom 5. If the Law had not first been given, the entire NT would have no meaning to us. If the Law were not given and given as Law, nothing would be able to restrain sin in our actions. Yet the Law in itself does not save us but condemns us because it cannot change our sinful hearts of keep us from breaking the Law of God's righteousness that is in the Law.
I'm having a really tough time following your logic in the above paragraph. What in the world does having the knowledge of God's righteousness have to do with curbing the actions of the recipients of his law? Your premise contradicts everything Paul taught about the Law! Yes...the Law is good, holy and righteous because indeed it does reflect God's character. But you know what? The law is powerless to change our character! Can the law change the spots on a leopard? Or change the color of the skin on an Ethiopian? Then neither can the letter of the law (that can only KILL) change our rebellious, God-hating hearts. And this is one of the huge differences between the two covenants: The New carries the unilateral promise of sovereign, effectual, supernatural action (a/k/a grace) that can change hearts, whereas the conditional, bitlateral Old offered no such remedy.
Compare it to natural laws of the land for a moment. The legal system of a nation may say if you murder you will be punished and punished severely. Does that stop all people from murder? Of course not. But for most it does, even if they would like to murder someone for some reason. The law restrains them, but it does not remove the sinful heart that would like to murder.
And this is precisely where your analogy breaks down, doesn't it? Yes, man's civil laws has restraining effects because men only look on the outside plus punishment is a lot swifter and surer. Yet, God looks primarily at our hearts. And when he does he sees far, far more "murderers" than civil authorities do! And if you still doubt me, read Paul universal indictment of all mankind in Rom 3:10-17. And if you do, take note of how many sins in that passage don't break man's civil laws! Yet, those laws are part of the universal indictiment against lawbreakers who break a much Higher Law numerous times a day -- lawbreakers whose consciences are so seared and hardened their conscience in many cases don't even accuse them.
So again, you have not proven the words of Calvin to be unbiblical, but simply divorced the two testaments from each other, and not actually paid attention to what Calvin was discussing or what he was saying. You presumed upon it what was not there based on what someone said about it (the book you mention)without observing their comment with critical thinking to see whether or not their argument was put forth with logical fallacies.
I would need you to present in your own words, as I am not going to go read a book in order to discover what it is you are presenting as an argument against Calvin's third function of the Law, in order to agree or disprove whatever is being suggested. But I will say this, going by the title of the book "No Sanctification by the Law" that Calvin's statement above does not say the Law is what sanctifies us or anyone who was under the Law. Notice in his statement the word "them". Who are the "them"? The one's under the Law. And what did the Law do? Informed them of the righteousness of God which they were to follow which is God's will. And to be obedient to them. It says not one word about sanctification, which is something the Holy Spirit does in actuality in those who are in Christ---and that too through His Word, not outside of it.[/quote from Arial]
I merely recommended the book because it goes into far more depth to the three uses than your three little paragraphs do.
Yes, sanctification is by the Spirit and the Word (a/k/a TRUTH). It is TRUTH (not to be confused with Law) that sets us FREE (Jn 8:32) -- something the Law of Moses could never do. In fact, the Law can only enslave us to sin! So, here's one contrast in Jn 1:17: Truth v. Law. Just as Christ is greater than Moses, so, too, is Truth greater than God's Law. Just as there is a qualitiative difference between the Two Greatest Commandments and all God's other commandments put together, so too there is a qualitative difference between Truth and Law.