Why Did the Law of Moses Exist?

I’ve been listening to a very good talk on Galatians 2-5 given by Christendom College’s Professor Eric Jenislawski called  “Saint Paul’s Galatians: Are You Saved?”  That talk, and countless others, are available free on the Institute of Catholic Culture’s website.

In it, he poses the question: Given how emphatically St. Paul denies that the Law of Moses can save us, why did God bother with the Mosaic Law at all?  Prof. Jenislawski does a great job of explaining the three answers Paul gives in Galatians 3.  Here are the three in a nutshell, taken from the handout (which is worth reading, by the way):

1. To prevent sin

Gal 3:19: “lt was added because of transgressions…
The most obvious rationale: God forbids certain behaviors in order to check evil.
2. To put to death self-righteousness
Gal 3:22: “But the scripture consigned all things to sin, that what was promised to faith in Jesus Christ might be given to those who believe.
Only when one knows just how sick one is, does one desire the physician.
Understanding the radical nature ofsin is an essential prerequisite to understanding the redemption that is offered in Jesus Christ. 
3. To chaperone Israel during its youth
Gal 3:24: “the law was our custodian (paidagōgos = disciplinarian) until Christ came.

That’s a great summary, and the rest of the handout serves as a good overview of Galatians 2-5 in general.  Following those three major points, here’s what Jenislawski said in his talk:

The next question is, “Why then the Law?” That’s Galatians 3:19. Because I imagine the Jews, the Jewish Christians, a little bit like the elder brother of the Prodigal Son, saying, “We’ve served you all these years, and now you’re telling us that to be justified before God you don’t have to keep the Law of Moses? What gives? What was its purpose? Just for nothing? Is God some kind of weird tyrant who says, ‘Today, if you want to be saved, stand on your left leg, and wear a funny hat. Tomorrow, three turtledoves’ It’s clearly not capricious or arbitrary, so what’s the purpose of the Law, if the Law doesn’t save?”

Do you see how that could be a natural question for Paul’s audience, who had previously been so Law-observant? So Paul gives three arguments for the Law. All of them show a sort of positive relationship between the Law, and the New Covenant of Jesus Christ. But all of them do this in a way that makes perfectly clear that it’s not like the Law begins to justify, and Christ finishes the job, or that the Law is sort of half of justification, or that justification is about the Law and Christ is a “plus One” on top of that, like cherry on the cake. There’s a certain relationship, but the Law does not justify. It only prepares for justification.

Paul steps through this in three steps. First argument for “why, then, the Law?” [is Galatians 3:19.] It was added because of transgressions. Why did God make so much Law? The same reason almost anybody makes law: people are doing stuff they shouldn’t be doing. That’s sort of a simple argument: since we’re pressed on time, I probably don’t have to further elaborate. If people weren’t sinning so much, God wouldn’t have to say “now, don’t do that, and don’t do that and don’t do that…” and there’s a lot of that in the Law of Moses. You can see that condemnation of people for doing bad things is important for getting them to ultimately do good things, but it’s not the same. Is that good?

Second, [Galatians 3:21], “is the Law against the promises of God? Certainly not.” So they’re not opposed. This is [Galatians 3:21-22]. “For if a law had been given which could make alive, then righteousness would indeed be by the Law. But the Scripture consigned all things to sin, that what was promised to faith in Jesus Christ might be given to those who believe.”

Now that’s a pretty radical statement. The Scripture consigned all things to sin, and by Scripture, he means the written Law of Moses, that’s what he’s talking about here, because this is an answer to “why, then, the Law?” So that’s pretty radical. What’s the purpose of the Law? To consign – RSV says “all things,” you could even read it “all” to sin. The second purpose of the Law is to say to Israel: SINNER! No, take it to heart, hear it one more time: SINNER! Sinner here, sinner there, that’s sin, that’s sin, that’s sin.

To be mean? No. Because only when Israel learns the radical nature of sinfulness can it appreciate what is offered in God’s grace. How often does Jesus in the Gospels attack self-righteousness? Not righteousness, but self-righteousness. “Because he wished to justify himself, he asked, ‘who is my neighbor?’” because that man wanted to come off squeaky clean, even though he hated Samaritans. Part of what Jesus does, constantly in the Gospel, is to teach people about the radical nature of sin. We can make the make the mess, and we can owe the debt, but we can’t pay it off by our own power. Only God’s grace can do that. God’s been trying to teach the human race that since Adam. And so an essential component leading up to understanding what is offered to you in the Cross of Christ, which is remission of your sins, and Redemption, justification, is understanding that it comes through grace and faith, and not by one’s own power.

Because a fallen man can do nothing to get himself out of the hole. And to do that, Israel had to be made constantly aware of its sinfulness. Because how often are the Jews, even with the sacrificial system, and the Ten Commandments, cheating on the Law and falling into this payoff mentality? “Ehhh, today not so good, extorted a bunch of poor people. Three oxen… done!” Kind of like you might do with MasterCard. $400 in debt, but okay, the bill comes, I cover it, I’m back to zero. That is not the relationship between a man’s sin and his power to get out of sin. It’s like stroking a check for $10 million on MasterCard, and the bill comes, and it’s like “Oh my gosh.” That’s why the Lord loves parables of crushing debtors. Remember the parable about the man who owes $10,000, and then he’s forgiven, and he throttles the guy who owes him a hundred? Or why Jesus who loves people who are in positions of medical infirmity who cannot be cured. Or prostitutes: once you’ve given yourself over to that kind of scarlet life, you can’t just do a series of actions, and get back to purity. Once you have leprosy, nothing under the sun can cure you (at least at that time). You have to have a certain kind of understanding that only God can make you whole. Or Augustine puts it this way: “Only once you know how sick you are do you ardently desire the physician.”

It’s a common mentality. Some people don’t like to go to the doctor: “ehhh, what’s he going to tell me? I don’t want to hear it.” And when the doctor tells you, “I’m sorry, you have cancer,” oh boy, do you sit up and take notice and love that physician. Because if you don’t, you’re dead. So the Scripture consigns all things to sin, lets people know the radical nature of sin, so that what was promised to faith in Christ may be given to those who believe.

So do you see how there’s kind of a dialectical relationship between the Law and Christ? The Law condemns precisely so Christ might bring justification. It’s not like one starts the process in a positive way, and the Other does the other 25%. The first one’s entirely negative: condemnation, so that once one’s on one’s knees, one can receive salvation from Christ.

Third argument gets us into what it means to be a good son or daughter of God, and the value of our human works. Paul says [Galatians 3:23-24], “before faith came, we were confined under the law, kept under restraint until faith should be revealed. So that the law was our ‘custodian,” (says RSV, literally paidagōgostrainer of children, chaperone, you could say), “until Christ came, that we might be justified by faith.”

Third argument is that the Law was fitted for Israel in its infant and adolescent stage of covenant history. Now “pedagogy” means “the art of teaching,” that’s not what it means in ancient Greece. It’s literally “disciplinarian.” Somebody who’s Johnny’s chaperone. Didn’t teach him, but brought him to school each day, carried his books, made sure he didn’t play hookie, didn’t hang out with the other Greeks who were drinking too much wine, gave him a slap when he stepped out of line. Kept him on the right path so that in adolescence, he might grow to maturity one day, internalize virtue, and not need the chaperone anymore. So too was ancient Israel under the Law. All kinds of rules and regulations, and Israel chafed under it sometimes, as a teenager does his father’s rules and regulations. But the purpose of that is that someday, you wouldn’t say, “Dad, please come tell me it’s ten o’clock and time to go to bed.” The purpose is that someday you’d be without that chaperone and disciplinarian because the Law is written in your heart. You don’t need the artificial enforcements about what’s right and wrong. You do what’s right, and avoid what’s wrong. So the third argument is covenant-historical.

For whatever it’s worth, the last of this arguments, the idea that the Law was our paidagōgos, is something I’ve talked about before.


  1. Great recommendation!

    I’ve just finished listening to talk there on Calvinism.

    There’s a really interesting bit during the Q&A where Dr. Marshner explains why so many Calvinists from New England became Universalists.

    Hmmm…reminds me of a blog entry I read recently… 😉

  2. “Why Did the Law of Moses Exist?”

    To act as a hedge for our protection (civil righteousness) and to act as a mirror to show us our sinfulness and great need of a Savior.

    That’s my Lutheran 2 cents.

  3. Restless Pilgrim, do you remember the name of the talk?


    Right on. The two reasons you cite are the first two of the reasons St. Paul and Prof. Jenislawski talk about (although his first point is a bit broader than “civil righteousness”, it certainly includes that). In addition to those two, Galatians 3:24 says that the law was our paidagōgos. Actually, I imagine you’d get a lot out of the talk, since you’re a guy who clearly loves the doctrine of justification by faith. I’m sure there are parts you’ll disagree with, but for most of the talk, I think you’ll come out seeing eye-to-eye.

    In Christ,


  4. I listened, Joe.

    Not bad but not quite there.

    We do have disagreements. The main one is that we believe the law is any demand which our existence places upon us and not merely the Mosaic Law.

    This understanding changes everything. and when you have been freed of the demands of the law(in Christ)…there is no going back (to any demands).

    Thanks, my friend.

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