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Sermon on the Mount: Fulfilling the Law

In the second century, some of the early church fathers thought the Old Testament was weird, kinda pointless, and should be cut out of the Bible entirely. (To be fair, some of them were, like many Romans, horribly anti-Semitic.) Nowadays, we realize that’s going way too far. Instead, some of us accomplish the same thing by just ignoring the Old Testament altogether.

So it’s not surprising that, when the New Testament mentions the Old Testament law, Christians have historically flailed around, not really knowing what to do with it. We’d like to just give it the boot, but the third imperative in the Sermon of the Mount is,

“Do not think that I’ve come to abolish the Law and the Prophets.” (Matt. 5:17)

Jesus is talking to a Jewish audience. The Law was the organizing center for their entire lives. Delivered to Moses on the top of Mt. Sinai, the Law is something you don’t mess with. But Jesus sure seems to be messin’. He’s about to quote the Law, then say, “But I tell you . . .” (Matt. 5:21-48). Before he gets started, he wants to be as clear as possible in Matt. 5:17-20–he is not giving the Law the boot.

You can think of the Law two ways.

First, you can think of it as the controlling document for the people of God–almost like a constitution. God makes a covenant with Israel, “I will take you as my own people, and I will be your God” (Ex. 6:7). The Law spells out how this relationship is going to work.

This points us toward some of the ways Jesus “fulfills” the Law (Matt. 5:17), but it’s complicated. We’ve been making a big deal of the old age that is doomed to pass away and the new age that is breaking in. This distinction is the driving force of Paul’s letter to the Galatians. He literally frames the entire letter in these terms. He introduces the whole thing by praising God for rescuing us “from the present evil age” (Gal. 1:4). And his final summary of the letter is that “what counts is the new creation” (Gal. 6:15).

So throughout the letter, Paul juxtaposes characteristics of the “present evil age” that we’ve been rescued from with characteristics of the “new creation” that we are now a part of. On the “old” side of this line, we have things like the flesh, slavery, and destruction. On the “new” side, we have the Spirit, freedom, and life (5:16-17; 4:31-5:1; 6:8). Which side is the Law on? Every time it is mentioned, the Law is solidly placed on the side of “this present evil age.”

That doesn’t mean that the Law is bad (but more on that later). It means that it is the controlling document for the people of God in the world that is passing away.

As someone born under the Law, Jesus took the curse of the law (Gal. 5:13). Christian thinking has gotten really confused about what “the curse of the law” is, but Paul is not the least bit subtle about what he means. There are two whole chapters in Deuteronomy (Deut. 27-28) that are all about “blessings and curses.” The point in these chapters is simple. In fact, Paul quotes it as a way of referencing those two chapters,

“Cursed is everyone who does not continue to do everything written in the Book of the Law.” (Gal. 3:10/Deut. 27:26)

What are these curses? All the nasty stuff in Deuteronomy 28—the things that start with “cursed will you be . . .”! If you don’t keep the Law, bad stuff will happen. That’s the agreement.

But here’s what Paul noticed: the Law itself says that you are cursed if you are hung on a tree (Deut. 21:23). Jesus was hung on a tree. But you are cursed if you break the Law. Jesus didn’t break the Law. In fact, he was sinless (John 8:46). An Israelite could sin, go through the appropriate steps to make atonement, and still come out with the status of “blameless.” “Sinless” is a standard that even the Law wasn’t looking for. But Jesus met it. He followed the Law to the letter.

So, reasons Paul, on the cross, Jesus is being cursed. But he didn’t break the Law. Therefore, he must be taking the curse for someone else (Gal. 3:13).

As Messiah, the one who embodies Israel, it turns out he’s taking the curse for everyone else. He is “the Lamb of God, who takes away the sin of the world” (John 1:29).

On the cross, Jesus takes the full curse of the Law. So where does that leave the Law? The deal was, if you break the Law, you get cursed. Israel broke the Law, and Jesus took the curse. So . . . what’s left? It kinda seems like it’s done. It’s run its course. “For through the law, I died to the law” (Gal. 2:19). What the Law said has “come to pass” (Matt. 5:18).

Also, to some extent, heaven and earth have passed away (Matt. 5:18). In the cross, something truly cosmic took place. When Jesus died, the entire old age died with him. When he rose, he rose as the first representative of the new age (Col. 1:18; Rev. 1:5). (So this new age becomes a reality for anyone who is “in him” [2 Cor. 5:17].)

Now, it may seem like a bit of a stretch to say that this is what Jesus means by “until heaven and earth disappear” (Matt. 5:18), but Peter quotes very similar language on Pentecost.

“I will show wonders in the heavens above . . . The sun will be turned to darkness and the moon to blood” (Acts 2:19-20/Joel 2:30-31). Peter says that this is what his audience is seeing (Acts 2:16). The outpouring of the Spirit is a visible sign of the passing of one age and the beginning of another. Apocalyptic language is entirely appropriate.

The prophets saw that this new age would bring a new covenant–a new agreement between God and his people (Jer. 31:31-34). When discussing Jeremiah, Hebrews describes something that is “new, of a different kind” (Heb. 8:13). It’s not replacing an apple with another apple. It’s replacing the apple with an orange. The new thing is fundamentally different.

So Paul, in Galatians, contrasts the two covenants (Gal. 4:24) and the two ages. For those living in the New Covenant, he actually talks about fulfilling the “Law of Christ” (Gal. 6:2). In the New Covenant, it’s not that Jesus nullifies the Law. He is the Law. In the New Covenant, the controlling document for the people of God is Jesus himself.

But seriously, the Old Testament Law takes up a good chunk of our Bibles. What are we supposed to do with it?

Well, if you want to know God’s heart, study it. That was the original point. The second way you can think about the Law is as a revelation of God’s heart.

Leviticus, one of the most regulation-heavy books in the Old Testament, is peppered with the phrase, “Be holy as I am holy” (e.g. Lev. 19:2). The point is that these rules God gave Israel weren’t arbitrary. God wasn’t like, “Hmm . . . should murder be right or wrong? I’ll go with wrong.” The rules are based on principles, and those principles are, in turn, based on the very character of God. For instance, murder is wrong because God is life. The rules are intended to show people God’s heart. As people follow them, they learn to be holy like he is holy.

That’s at least one reason why it’s never going to be a good idea to discourage anyone from following them (Matt. 5:19). That’s also why even Paul himself is apparently still celebrating the Jewish feasts (Acts 20:16) and even associating himself with sacrifices decades after the crucifixion (Acts 21:24). Because the Law points to God and is fulfilled in Christ, Christianity had no trouble incorporating Jews who were still “zealous for the law” (Acts 21:20-21).

The Law can point people to God’s heart.

But that’s the problem. It can point to God’s heart. But nothing says that it necessarily will. It has always been true that there was the letter of the Law and the spirit of the Law (cf. 2 Cor. 3:6). And it was always possible to keep the letter, but miss the spirit entirely. A person could follow all the rules, but make no connection with the deeper principles, much less God’s heart.

The prophets spent a lot of time pointing out this kind of thing. Ancient Israel often focused on getting the sacrifices right, but overlooked actually being the kind of people God called them to be (Micah 6:6-8). Maybe they just flat-out ignored some of the laws. Well, the Pharisees fixed that. But nit-picking about the letter of the Law still didn’t get them to the heart of God. That was the core of Jesus’ problem with them (cf. Matt. 23:16-28).

That’s what Jesus means by, “Unless your righteousness surpasses that of the Pharisees and the teachers of the law, you will certainly not enter the kingdom of heaven” (Matt. 5:20).

The failure of the ultimate rule-keepers to take on the heart of God shows the failure of focusing on rule-keeping itself.

And that’s the tragedy of thinking that the rest of Matthew 5 is just Jesus giving an even stricter set of rules. In Matthew 5:21-48, Jesus is calling out the fancy footwork people do to keep the letter of the Law while missing the heart. Make his statements into a new list of rules, and people will find a way to dance around them, too.

Instead, Jesus is pointing to the heart.

This calls for a New Covenant–one that can put the principles of the Law, the spirit of the Law, on peoples’ hearts (Jer. 31:33). Paul makes the analogy of the Law as a guardian (paidagogos), kind of training and supervising the kids until they grow up (Gal. 3:23-25).

In interesting ways, that mirrors peoples’ actual moral development. Kids need rules. They have no clue what’s a good idea, what’s a bad idea, or how they should be in the world. They need something external to guide them. But part of growing up involves internalizing the principles involved in these rules. Once you have a strong moral compass, you don’t need to refer to rules all that much.

It’s almost like that’s what God did with humanity.

Israel was grateful for the Law because they saw that it gave them a leg-up on the nations around them (Ps. 19:7-12; 119:1-16). The creator of the universe had given them guidance on how to be in the world. So, as Paul says, “The law is holy, and the commandment is holy, righteous and good” (Rom. 7:12). The only problem, which Paul hammers at so brutally, is that it was external. It couldn’t change anyone. (But it sure could condemn them!)

Looked at in the best light, the Law raised people up and trained them until, in the New Covenant, they grew up. People could get a new heart. The principles were internalized so they could live the heart of God from the inside out.

But again, this doesn’t nullify the Law. The spirit of the Law is what really matters.

Jesus and Paul both seem to make the argument that to fulfill the spirit of the Law is to fulfill the Law. Jesus’ argument against the Pharisees clearly shows that fulfilling the letter is not sufficient for fulfilling the spirit of the Law. But he and Paul both seem to indicate that it’s not necessary, either. If someone fulfills the spirit of the Law, absent of the letter, it still counts. (This makes even more sense if the Law of Moses is no longer the controlling document for the people of God).

What else could be the point of statements like, “Whoever loves others has fulfilled the law” (Rom. 13:8-10)? Or, “Do to others what you would have them do to you, for this sums up the Law and the Prophets” (Matt. 7:12)? If you’ve lived out the heart of God, you’ve fulfilled the Law. That, after all, is what the Law was aiming at all along.

So it’s pretty much exactly what Jesus said. He did not come to abolish the law, but to fulfill it. In his life, he followed it to the letter. In his death, he brought it to its culmination. And as we live in him, the Law is fulfilled in us as we live out the heart of God.

If you’ve lived out the heart of God, you’ve fulfilled the Law.

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