Do You Not Teach Yourself?
Do You Not Teach Yourself?
Text: Romans 2:17–29
Key Verse: Romans 2:21 (NIV) "You, then, who teach others, do you not teach yourself? You who preach against stealing, do you steal?"
Introduction: The Gap Between Name and Reality
There was once a pasta restaurant in a Seoul alley that boasted waiting times of over an hour. Rumors about its food spread, photos were shared, and it was featured on broadcast shows, causing its brand value to skyrocket. Then, one day, customers completely vanished. It was because a video exposing the kitchen interior went viral. The hygiene inside was nothing like the reputation outside, and the brand built over years collapsed overnight.
The gap between name and reality. The dissonance between brand and substance. Today’s text addresses precisely this. Yet Paul’s indictment is not about a restaurant. It is about God’s own people, those who live under the name of God.
Last week, in Romans 2:1–16, we learned that God’s judgment falls on those who condemn others while committing the same sins themselves. Today’s passage, verses 17–29, extends that argument with even sharper precision. Paul now narrows his target, taking aim specifically at the Jews.
This indictment does not feel unfamiliar to us today because this was not merely a Jewish problem. The pitfall they fell into can just as easily be repeated by Christians today. To avoid it, what must we hold onto? The text unfolds in three directions.
I. Do Not Rest on Your Name
"You who call yourself a Jew; you rest on the law; you boast in God..." (v. 17)
Paul’s opening shot begins with the address, "you who call yourself a Jew." Jewish identity was never merely an ethnic label. It was essentially religious. The same holds true today: conversion to Judaism formally makes one Jewish, regardless of bloodline.
So what constituted this Jewish identity? Verse 17 points to two things: resting on the law and boasting in God. And this boasting was not groundless; it had clear grounds.
"...You have been instructed out of the law; you know his will; you approve what is superior..." (v. 18)
The phrase "instructed out of the law" comes from the Greek katēcheō, the same root as the English "catechism." It refers not to a casual hearing but to regular, systematic instruction. Jewish children in the first century began memorizing the Pentateuch at age five, the Oral Torah at ten, and engaging in advanced theological debates by fifteen. At home, the Shema (Deut. 6:4) was recited morning and evening; in the synagogue, rabbis provided structured teaching. The Sabbath regulations alone were so precise that they dictated everything from permissible walking distance to the exact weight one could carry.
Built on this foundation of religious training and moral education, Jewish self-conception was expressed in fivefold terms:
"...You are sure that you are a guide for the blind, a light for those who are in darkness, an instructor of the foolish, a teacher of children, having in the law the embodiment of knowledge and truth." (vv. 19–20)
Though five, they all point to one reality: blind, in darkness, foolish, children—these all referred to Gentiles. Jews saw themselves as the beacon illuminating the dark world, the guides leading the blind.
How would this sound in our language?
"The UBF shepherd called by that name, relying on the Word of God and boasting in Him, having undergone systematic Bible study and education to discern His will and that which is excellent, confident that I am a shepherd guiding the blind, a missionary shining light to those in darkness, a teacher of the Bible—thus I trust in myself."
Only the name differs; the story is the same.
This identity and self-perception are not inherently wrong. Resting on the law, boasting in God, studying the Word systematically to discern good from evil, guiding the blind, shining light in darkness—these are all good, beautiful, and necessary.
Yet a crucial phrase is inserted at the end of verse 20: "thus you trust in yourself." This phrase is deeply significant. To "trust in yourself" implies there is no guarantee that others, or God, see it that way. God may see entirely differently. Identity and self-perception are not enough. That single phrase already foreshadows Paul’s ensuing indictment.
May we not rest behind the name "Christian," but instead honestly examine ourselves before this Word.
II. Prove It by the Fruits of Your Life
Now Paul’s exclamation begins:
"You, then, who teach others, do you not teach yourself? You who preach against stealing, do you steal? You who say that people should not commit adultery, do you commit adultery? You who abhor idols, do you rob temples?" (vv. 21–22)
The problem is not teaching itself, but failing to apply that teaching to oneself. Paul does not offer abstract moralism; he lists three specific sins: stealing, adultery, and idolatry. These are core commandments of the Decalogue. Yet those who relied on and taught the Law were violating its very foundation.
Here, "stealing" is not merely petty theft. Embezzling public funds counts too. This refers to a real event in first-century Rome. Jewish teachers approached a Roman noblewoman named Fulvia, built trust by teaching her Jewish law, and collected donations for the Jerusalem temple. But the funds were embezzled and used privately. When reported to Emperor Tiberius, he expelled 4,000 Jews living in Rome. This incident is recorded by the ancient historian Josephus in Antiquities of the Jews 18.6.3. The Roman Christians receiving Paul’s letter would have remembered it vividly.
Bring this to our context, and the scenes we see in the news today come to mind easily: financial scandals and sexual immorality among church leaders—exactly the two sins Paul indicted two millennia ago, repeating themselves within the church.
What is the result?
"For, as it is written, ‘The name of God is blasphemed among the Gentiles because of you.’" (v. 24, quoting Isa. 52:5)
In Isaiah’s original context, this refers to Israel’s exile in Babylon. When Gentiles saw the captives, they mocked, "Where is their God?" Israel itself provided the excuse. Paul declares that this same historical pattern is repeating now.
God is invisible. What the world sees is the lives of those who claim to believe in Him. When that life contradicts their words, people think, "Even if they believe in God, look at how they live. What good is belief?" The honor of God is damaged by our lives.
When I was young, there was a pharmacist in my neighborhood. Enthusiastic about evangelism, he would hand out a gospel tract to every customer. But one night, he absconded with all the money he had collected from families. After that, the neighborhood never heard the gospel again. Every time someone mentioned it, his face came to mind. The gap between one man’s words and his life completely shut the door through which the gospel could enter.
The apostle Paul writes in 2 Corinthians 3:2, "You yourselves are our letter, written on our hearts, known and read by everyone." The Bible the world reads is our daily life. Before loud proclamations of the gospel, we must first stand before the world with a quietly radiant character. The world is not moved by our biblical knowledge. They are won by the scent of a life: calmness in suffering, integrity even at personal cost, warmth toward the vulnerable. That is how hearts are opened.
III. Receive Circumcision of the Heart
If life contradicts identity and self-perception, anxiety is inevitable. Yet Jews had an inner insurance policy: "We are the circumcision people of God. Surely we won’t lose salvation." That complacency existed.
Paul strikes it directly:
"For circumcision indeed is of value if you obey the law; but if you break the law, your circumcision becomes uncircumcision. So then, if those who are uncircumcised keep the requirements of the law, will they not be regarded as though they were circumcised?" (vv. 25–26)
Circumcision is a necessary but not sufficient condition. If circumcised, live accordingly. If circumcised yet break the law, your circumcision loses its efficacy.
In New Testament terms, circumcision parallels baptism. Baptism is a public declaration and seal of faith in Christ, signifying rebirth. It is like a wedding: two people in love might not need a ceremony, but the ceremony formalizes the relationship and vows. Similarly, baptism has significance, but a baptism certificate does not guarantee salvation if there is no faith or new life. The baptism only bears full weight when lived out in faith.
Then Paul drops a bombshell Jews never expected:
"Will not those who are naturally uncircumcised but keep the law condemn you who, though you have the written code and circumcision, break the law?" (v. 27)
Jews imagined the final judgment with Gentiles in the defendant’s dock and Jews in the prosecutor’s holding the Law. But Paul reverses it: Jews in the dock, and uncircumcised Gentiles who lived out the Law’s substance as prosecutors. For Jewish hearers, this was explosive.
Where, then, does Paul point as the ultimate direction?
"No one is a Jew who is merely one outwardly, nor is circumcision merely outward and physical. No, a Jew is one inwardly; and circumcision is circumcision of the heart, by the Spirit, not by the written code. Such a person’s praise is not from human beings but from God." (vv. 28–29)
"Outward" refers to visible, external things; "inward" to the invisible, internal reality.
Christians also have external markers of faith: attending Sunday worship, posting a verse as a profile picture, praying before meals. But these are not the core. True Christian identity lies in the heart. Jeremiah foretold this: "'I will put my law in their minds and write it on their hearts.'" (Jer. 31:33). Not the Law on stone tablets, but on the tablets of the heart—the essence of the New Covenant.
What does it mean for the heart to change? Christian philosopher James K. A. Smith, in his book You Are What You Love, describes heart change as "a shift in what you love." True transformation is a change in what you most cherish and love. No external law can accomplish this. Strict discipline can regulate behavior, but it cannot change the object of your love. Just as a child raised in a strict household may pray and attend church with a grimace, that discipline cannot transform the deep desires of the heart.
Only one can change the heart. The answer lies in verse 29: "by the Spirit." The Holy Spirit. The Spirit indwells believers, transforming and renewing us. This is why Paul repeatedly urges, "Walk by the Spirit." Ezekiel prophesied: "I will give you a new heart and put a new spirit in you; I will remove from you your heart of stone and give you a heart of flesh. And I will put my Spirit in you and move you to follow my decrees." This is fulfilled in Christ through the Spirit.
One more detail: the word "praise" in verse 29. Why mention praise here? The root of "Jew" (Judah) tells us. Judah, fourth son of Jacob, comes from the Hebrew יְהוּדָה (Yehudah), meaning "praise." Genesis 29:35 records Leah’s words: "This time I will praise the Lord." Paul, addressing an audience that knew this etymology, is essentially asking: "Your name means 'praise.' Whose praise are you seeking?"
The Jews’ hypocrisy stemmed from here: they sought praise from people. They wanted fellow Jews to call them "true Jews." Even when the heart and life didn’t match, they performed. Eventually, it was exposed. Jesus pinpointed this in Matthew 6:1: "Be careful not to practice your righteousness in front of others to be seen by them." Alms, prayer, fasting—all become performances when done for human eyes.
The solution is clear: seek God’s praise. Live before God, not people. Reformers expressed this beautifully in Latin:
Coram Deo — before the face of God.
Luther and Calvin proclaimed this in unison. The corruption of medieval Catholicism came from departing from Coram Deo to pursue Coram Homine (before people). When external rituals became the basis of authority and pleasing human eyes occupied the place of faith, the community collapsed from within. The Reformers saw this structure and cried out to return to God alone. Our only audience is God. When we live conscious of Him, we no longer need to navigate human expectations.
We must hold to two things: rely on the Spirit within, not merely the written code. The Spirit alone can transform us. And live before God, not before people. Miss these two, and the gap between knowing and living widens until it collapses.
Conclusion: Remove the Mask, Stand Before the Mirror
Paul could pierce the Jews’ hypocrisy so sharply because he knew it from the inside. Paul himself was one of them. In Philippians 3, he confesses: "circumcised on the eighth day, of the people of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; as to the law, a Pharisee." He boasted in the law, trusted in identity, and vigorously condemned others by that same standard. Thus, he knew the trap’s structure better than anyone.
Yet an event changed Paul’s life: his encounter with the risen Christ. On the Damascus road, when Christ appeared in blinding light (Acts 9), everything he had built—identity, self-perception, achievements—was instantly reevaluated. He called it "rubbish" compared to knowing Christ Jesus his Lord (Phil. 3:8). Not because those things were evil, but because Christ far exceeded them in value.
Why such a radical change? Because Jesus bridged the gap we cannot. The gap between knowing what we should do and failing to do it. The gap between teaching others what we fail to live. We all have it. We know we shouldn’t live like this, yet we cannot. The written code cannot change the heart.
But Jesus came to bridge that gap. He stood where we deserved condemnation. He bore the judgment we owed. Ascending, He sent the Spirit to transform our hearts. Romans 8:3–4 declares: "For what the law was powerless to do because it was weakened by the flesh, God did by sending his own Son in the likeness of sinful flesh to be a sin offering. And so he condemned sin in the flesh, in order that the righteous requirement of the law might be fully met in us, who do not live according to the flesh but according to the Spirit." What the law could not do, Christ and the Spirit accomplish.
Therefore, this text is not meant to crush us. It is a mirror designed to lead us to Christ. "I am a teacher who does not teach myself." Hold to that honest confession, approach Christ, and the Spirit works within.
"You who call yourself a Jew"—hear this in the language of today:
"I, called a Christian, relying on the Word and boasting in God, confident that I am a light to those in darkness—yet do I stand before that Word myself?"
May this week be one where we bring this question to the Spirit and go forward.
Chang-Moo Lee / 2026 Romans Lesson 4