“The third use of the Law (being also the principal use, and more closely connected with its proper end) has respect to believers in whose hearts the Spirit of God already flourishes and reigns. For although the Law is written and engraven on their hearts by the finger of God, that is, although they are so influenced and actuated by the Spirit, that they desire to obey God, there are two ways in which they still profit in the Law.”

In his Institutes of the Christian Religion, Calvin talks about three parts, or uses, of the law (I.II.VII.6-12).  First, he said, the law “warns, informs, convicts, and lastly condemns, every man of his own unrighteousness. …The law is like a mirror.  In it, we contemplate our weakness….”  Second, Calvin said the law restrains people by the fear of punishment: “The law is like a halter to check the raging and otherwise limitlessly ranging lusts of the flesh.”  What did he say about the third use of the law?

“The third use of the Law (being also the principal use, and more closely connected with its proper end) has respect to believers in whose hearts the Spirit of God already flourishes and reigns. For although the Law is written and engraven on their hearts by the finger of God, that is, although they are so influenced and actuated by the Spirit, that they desire to obey God, there are two ways in which they still profit in the Law.”

The “two ways” Christians can profit from the law are:

 1) It teaches us the will of the Lord.  “It is the best instrument for enabling them daily to learn with greater truth and certainty what that will of the Lord is which they aspire to follow.  …Let none of us deem ourselves exempt from this necessity, for none have as yet attained to such a degree of wisdom, as that they may not, by the daily instruction of the Law, advance to a purer knowledge of the Divine will.”

2) It exhorts us to and encourages us in obedience: “The servant of God will derive this further advantage from the Law: by frequently meditating upon it, he will be excited to obedience, and confirmed in it, and so drawn away from the slippery paths of sin.  On this theme, Calvin says that in Psalm 119 the prophet “proclaims the great usefulness of the law: the Lord instructs by their reading of it those whom he inwardly instills with a readiness to obey.  He lays hold not only of the precepts, but the accompanying promise of grace, which alone sweetens what is bitter.”

I appreciate how Calvin said the third use of the law is the principle part, or use.  This is one reason why the Reformed/Presbyterian catechisms have a large section on the 10 commandments as they apply to the Christian life.

Right after Calvin mentioned this, he spoke against those who think we do not need the law (the Libertines and Antinomians):

Some unskillful persons, from not attending to this [the third use of the law – spl], boldly discard the whole law of Moses, and do away with both its Tables, imagining it unchristian to adhere to a doctrine which contains the ministration of death. Far from our thoughts be this profane notion!

Moses has admirably shown that the Law, which can produce nothing but death in sinners, ought to have a better and more excellent effect upon the righteous. When about to die, he thus addressed the people, “Set your hearts unto all the words which I testify among you this day, which ye shall command your children to observe to do, all the words of this law. For it is not a vain thing for you; because it is your life,” (Deut. 32:46, 47.)

If it cannot be denied that it contains a perfect pattern of righteousness, then, unless we ought not to have any proper rule of life, it must be impious to discard it. There are not various rules of life, but one perpetual and inflexible rule; and, therefore, when David describes the righteous as spending their whole lives in meditating on the Law, (Psalm 1:2,) we must not confine to a single age, an employment which is most appropriate to all ages, even to the end of the world.

Nor are we to be deterred or to shun its instructions, because the holiness which it prescribes is stricter than we are able to render, so long as we bear about the prison of the body. It does not now perform toward us the part of a hard taskmaster, who will not be satisfied without full payment; but, in the perfection to which it exhorts us, points out the goal at which, during the whole course of our lives, it is not less our interest than our duty to aim. It is well if we thus press onward. Our whole life is a race, and after we have finished our course, the Lord will enable us to reach that goal to which, at present, we can only aspire in wish.

This quote can be found in John Calvin and Henry Beveridge, Institutes of the Christian Religion, vol. 1 (Edinburgh: The Calvin Translation Society, 1845), 419–420.

Rev. Shane Lems is a minister in the Orthodox Presbyterian Church and services as pastor of Covenant Presbyterian Church in Hammond, Wis. This article appeared on his blog and is used with permission.