The Justification Equation (Galatians 2:15-21)


This sermon is part of a series on Galatians titled “Justified.” Previous sermon: “Christian Accommodation (Galatians 2:1-14).”

Big Idea: God’s grace plus your faith equals justification.

God’s grace plus your faith equals justification. However, this does not mean that your faith saves you. Salvation is by grace alone. In Romans 3:21-25, Paul writes:

21 But now the righteousness of God has been manifested apart from the law, although the Law and the Prophets bear witness to it – 22 the righteousness of God through faith in Jesus Christ for all who believe. For there is no distinction: 23 For all have sinned and fall short of the glory of God, 24 and are justified by his grace as a gift, through the redemption that is in Christ Jesus, 25 whom God put forward as a propitiation by his blood, to be received by faith. [emphasis added]

Two important observations:

  1. Salvation is a gift of grace, period.
  2. Those who believe accept the gift of salvation.

From this, we can derive two theological points:

  1. Grace is what saves us.
  2. Faith is the condition.

When we come to Paul’s comments in Galatians 2:15-21, we must keep this in mind because some may misunderstand Paul to be suggesting that our faith saves us.

Our faith does not save us. Grace is what saves us. Faith is the condition.

Most Bibles place a division between 2:14 and 2:15. However, it is likely that 2:15-21 is a continuation of Paul’s rebuke to Peter in Antioch (Moo, Galatians, 153; Schreiner, Galatians, 150). This is important because it gives us Paul’s theological reflection on what happened in Antioch, which was:

  1. Peter had been fellowshipping with the Gentile believers.
  2. Jewish believers sent by James arrived.
  3. Peter stopped fellowshipping with the Gentile believers out of fear of being criticized for eating with unclean people.
  4. Peter influenced others in his error.
  5. Paul rebuked Peter publicly for not exemplifying the truth of the Gospel; that is, the grace of the Gospel.

Now Paul is going to reflect on the theological reasons for his rebuke of Peter:

  1. The Believer’s Righteousness (2:15-16): A person is justified through faith, not through rule-keeping.
  2. The Believer’s Rule-Keeping (2:17-18): A believer who reverts to depending on rule-keeping for justification, transgresses the Gospel of Grace.
  3. The Believer’s Residency (2:19-20): Those who reside in Christ are no longer condemned by the law. The law is not the standard (nor has it ever been) by which we are deemed righteous (right with God).
  4. The Believer’s Reliance (2:21): To return to rule-keeping for justification is to deny the purpose of Christ’s death. 

The Believer’s Righteousness (2:15-16)

In verse 15, the “we” refers to Paul, Peter, and other believing Jews. They are “born” into the people of God unlike Gentiles, who Jews consider to be “sinners.” The reason Paul brings this up is because he wants to rid us of the thought that being born a Jew somehow gives him or Peter an “inside track.” 

Let me illustrate: The inside track is the lane nearest the center of the course. Naturally, a person who runs on the inside of the track has a shorter distance to run than the person on the outside of the track. So, to make it fair, the outside lane starting lines are moved up. Similarly, the Jews commonly thought they had the inside track on access to God. In one sense they did for God had revealed Himself to them especially. But in the most important sense – spending eternity with God – the Jews were no more special than anyone else.

“Yet we know that a person is not justified by works of the law but through faith in Jesus Christ…” (2:16). This is one of the most important verses in Galatians (Schreiner, 167). Paul immediately debunks the idea that being born a Jew is good enough to justify a person. In the same way, being born into a conservative, evangelical church-going family no more saves you than being a Jew saved Paul. In Paul’s case, it took a pretty radical conversion experience. You may not experience such a radical conversion, but the truth remains, one is not saved because of the conditions into which they are born; salvation is through the grace of Christ alone.

Furthermore, Paul clarifies that it is not by the works of the law, that is, by rule-keeping, that anyone is justified. “Yet [because] we know…” indicates that none of these Jewish agitators denied Christ, they just had a different equation: 

Justification = grace through faith + works of the law

The phrase “works of the law” simply means “rule-keeping” or doing what the law requires. The word “law” appears thirty-two times in Galatians, and every time, with one exception (6:2, “the law of Christ”), it refers to the law of Moses (the 613 rules). In chapter 3, we will look in more detail as to what the purpose of the Law of Moses was.

The main point of 2:15-16 is that the believer’s justification does not come about because of rule-keeping. One does not gain a right relationship with God by rule-keeping. This in no way undermines rules or rule-keeping, but it puts it in its theological place—rule-keeping is an expression of faith, not the earning of grace. It is also important to note the word “justified” here is present tense, which refers to our present and ongoing state of being right with God. This means that justification is not a one-time event and you’re forever good to go.

The Believer’s Rule-Keeping (2:17-18)

“But if, in our endeavor to be justified in Christ, we too were found to be sinners …” (2:17). Paul here implies what he will explain in 2:20, that being reconciled to God is based on our union with Christ—we are only “justified in Christ.” But why would a person who is in Christ be found a “sinner”? 

We should understand Paul’s use of “sinners” here with quotations. Let’s go back to Peter’s behavior at the dinner table for a moment. Peter knew that Paul and the Gentile believers were as much “in Christ” as he or any of the Jewish believers were. But when his brothers from Jerusalem arrived, he treated the Gentiles like “sinners.” This is exactly why Paul rebuked Peter. So Paul explains, “But if, in our endeavor to be justified in Christ, we too were found to be sinners, is Christ then a servant of sin?” Certainly not!

Peter did the opposite of what Jesus did in Luke 5:29-30: “And Levi made Jesus a great feast in his house, and there was a large company of tax collectors and others reclining at table with them. And the Pharisees and their scribes grumbled at his disciples, saying, ‘Why do you eat and drink with tax collectors and sinners?’”

Again, “sinners” in 2:17 should have quotation marks around it. Jesus’ fellowship with sinners did not make him a servant to sin; that is, he did not lead people to sin. Jesus ate with sinners, but He didn’t sin with sinners. Likewise, the Gospel of Grace which was revealed to the apostles does not encourage sin or lead people to sin. Rather, it provides the basis for our obeying God out of love rather than guilt. It’s absurd to think that anyone who is reconciled with God—justified—remains a categorical sinner. That’s Paul’s point. Yet, remember, that’s how Peter’s actions toward the Gentiles would be understood by the Gentiles when they saw him leave them and move to the “clean” table.

Now, as we work through Paul’s doctrine of justification, we have to notice that he consistently walks between two pitfalls—one is legalism (that we are saved only after we have kept certain rules); the other is antinomianism (that we are saved and the rules don’t matter).

“For if I rebuild what I tore down, I prove myself to be a transgressor” (2:18). What did Paul tear down? The belief that one is justified by rule-keeping. What is it that Paul would do that would “rebuild” the same kind of edifice he had torn down? Preaching that one is saved by grace but kept by rule-keeping. What one hand takes away, the other gives back. In other words, it does no good to be strong on reconciliation with God by grace alone, then preach a works-based salvation that says one’s ongoing reconciliation with God is based no longer on grace, but on their rule-keeping. If a believer accepts justification by grace, then tries to maintain justification by rule-keeping, they transgress or sin against the Gospel of Christ.

Imagine that you bought an old, dilapidated house, hoping to tear it down and build a new one. The floors are rotted, the drywall and carpets are moldy, the roof is leaky, the foundation is crumbling, and…well, you get the picture. So you begin to take the house apart piece by piece, saving every rusty nail, every rotten board, every moldy piece of drywall, and every broken shingle. Finally, you finish your delicate and detailed disassembly of the old house. Now, it’s time to put up the new one. You reset the same broken blocks for the foundation, you lay down the same rotten boards for the floor, you reconstruct the same moldy walls and install the same old carpet, and even put the same broken shingles back in place. Do you have a new house? No, you’ve merely wasted your time.

This is exactly the picture that Paul is painting in 2:18. The old house is all about being saved by works. The new house is all about being kept by works. There’s no improvement—it’s the same old house.

The Believer’s Residency (2:19-20)

“For through the law I died to the law, so that I might live to God” (2:19). The Law was never intended to be treated as a way of earning justification. Rather, the Law is God’s means for showing us how to live in a right relationship with Him. Rule-keeping is what people do to show their love for God.

But what does Paul mean by saying “I died to the law”? Two passages from Romans helps to clarify this for us:

  • Romans 6:2, “How can we who died to sin still live in it?” 
  • Romans 7:4, “You also have died to the law through the body of Christ….:

Similarly, Paul asks Galatians 2:19, “How can we who died to the law still live by it?” The answer we can derive from the Romans passages is that to die to the law is to stop trusting in rule-keeping as our means for being acceptable to God.

To die to the law is to stop trusting in rule-keeping as our means for being acceptable to God.

“I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me” (2:20). There are two parallel lines in vv. 19-20. The old “I” and the new “I”; the old “self” and the new “self.” The new begins with our identity with Christ. This reminds me of Romans 6:6, “We know that our old self was crucified with him in order that the body of sin might be brought to nothing….”

When you move to a new state, you don’t automatically become a resident of that state. For instance, when we moved back to Indiana, I had to “establish residency” by showing the proper documentation that we were truly living in the state. It is simple but indispensable. In order to be a new you, you must establish residency in Christ. In other words, there’s no reconciliation, no residency in salvation, apart from being united with Christ through faith.

Paul puts this in terms of crucifixion. How do we identify with Christ? By giving ourselves up to spiritual crucifixion. Jesus put it this way in Luke 9:23, “If anyone would come after me, let him deny himself, take up his cross daily, and follow me.” The cross is the solution to the problem uncovered by the law – human rebellion. 

Juxtaposed against this identification with Christ’s death as the destruction of the old “I,” the new “I” in union with Christ now lives “by faith in the Son of God” (2:20). “Love is the fuel of faith” (Schreiner, 173).

The Believer’s Reliance (2:21)

Paul continues: “I do not nullify the grace of God, for if righteousness [being made right with God] were through the law, then Christ died for no purpose” (2:21, parenthetical explanation added). There are two ways to nullify grace:

  1. Receiving grace then living like it’s not dependable.
  2. Receiving grace then living like it doesn’t matter.

The following newspaper report gives a striking illustration of this:


CRESCO, Iowa (AP) — Officials say a small county-owned bridge in northeastern Iowa has collapsed after a semitrailer weighing more than 10 times the bridge’s weight limit drove across it.

Winneshiek County Engineer Lee Bjerke says the collapse happened early Friday morning on Cattle Creek Road over the Upper Iowa River east of Cresco.

Bjerke says the small bridge had a weight limit of 3 tons (2.72 metric tons), about the weight of a pickup truck. A sign warning of the span’s limit was clearly posted. But Bjerke says a loaded grain truck estimated at more than 30 tons (27.22 metric tons) tried to cross it, causing the collapse. No one was injured.

Canoes and other water crafts have been barred from the stretch of river until debris from the collapsed bridge is cleared.

Just like the bridge in this story, our rule-keeping could never be enough to establish a right relationship with God. Trusting in rule-keeping is like building a bridge of cardboard.


Earlier Paul used the image of construction. When a large building is constructed in a city like Chicago or New York, the only way to assure a secure foundation is to anchor the building to the bedrock. There’s no way to build a solid edifice without the security of the bedrock. You and I never see what all is going on below the surface level, but the reason we feel safe going up forty or fifty floors is because of our faith that the building is secured below us. The grace of Christ is our bedrock. Nothing else holds the house up. To be certain of this truth, Paul repeats himself in 2:16, “by the works of the law no one will be justified.”

There are many seekers after Christ who feel like they have to comply or be “good enough” for grace. I tell you on the basis of Galatians and the biblical doctrine of justification, that none of us can ever be “good enough” to merit the grace of Christ. There is no sense in which you must first be “sanctified” in order to be good enough to be justified. Perish that thought and come just as you are. Christ died for the ungodly to grace to sinners that through Him, and Him alone, we might be saved.

David Fry
David Fry
Senior Pastor at the Frankfort Bible Holiness Church. PhD in Systematic Theology (Trinity Evangelical Divinity School). MDiv in New Testament Theology (Wesley Biblical Seminary).