Though we may believe we are justified by faith, sometimes we still want to live by the law. In this passage, Paul helps us see why if we really understand the law, we won’t want to live under it.


Galatians 4:21-31

Galatians (Zondervan Exegetical Commentary on the New Testament), Tom Schreiner

Galatians (Geneva Commentaries), John Brown

Galatians (Crossway Classic Commentaries), Martin Luther

Galatians For You, Timothy Keller

Sermon Transcript

A common experience of parents is trying to help your kids sort out their desires. This summer on vacation we went to a toy store, always a risky move as a parent of young children. My son saw a bocce ball set that he wanted, and as I thought about it some, I thought, “That could be really cool.” We could play it with his cousins while on vacation; it might become the hit of the whole vacation! But then he saw a little toy cow, where if you put little balls in its mouth and squeeze it, it shoots the balls out. And suddenly, that’s what he wanted more than anything else. I’m thinking this is gonna get played with for 5 minutes and never touched again, but how do I convince him of that? How do I tell him, “No, I know you think you want this, but if you really understood these two options, you wouldn’t want this one!” That’s the kind of appeal Paul makes in this passage. The churches of Galatia had been saved by believing the gospel: God’s promise of eternal life to whoever believes in Christ, but now another option presented itself: False teachers were telling them they also needed to keep the law God gave to Moses. And that was attractive to them. We also struggle to live by faith in God’s promise, and are prone to look to our efforts. I’ve sometimes felt like, “I wish salvation were by works, because then I would just do the works, and get someone to videotape me doing them. Then anytime I felt insecure, I’d watch the video and reassure myself.” The law looks attractive for that reason: It gives us something to do, that we can see and rely on. But in this passage we learn that as attractive as it may appear, you don’t want to live under the law, and we see three reasons: The law operates by the flesh, the gospel by the promise; the law produces slavery, the gospel produces freedom; and those of the law are your enemies, not your friends.


The law operates by the flesh, the gospel by the promise


Our passage begins with Paul’s basic appeal to the churches of Galatia in this section: Look, you’re being tempted to go live under the law. These false teachers are telling you you must be circumcised and observe the Jewish calendar, which I’m telling you means you must keep the whole law given to Moses. Maybe you’re still thinking that’s a good idea. And maybe you’re here today thinking, “I think I can do this whole Christianity thing. I get it: I have to give up getting drunk, I have to stop having sex with people to whom I’m not married, I have to not swear, I have to come to church, I have to read my Bible, I have to give some of my money away, and I should probably volunteer occasionally. I’m done with all those years of partying; it’s time to settle down. Sign me up.” If that’s your picture of what it means to be a Christian, you’re essentially signing up to live under the law, though in my example it’s not the law of Moses. And what Paul is saying here is that if you really listened to God’s law, you wouldn’t want to do that.


Why? Paul goes back to a story in the law, another story from the life of Abraham. Recall that Abraham is a very important figure in Paul’s dispute with the churches of Galatia, and one point of the debate has been who are the true children of Abraham. God promised eternal life to the children of Abraham, so it’s a big deal to be a child of Abraham. God also told Abraham to mark his children with the sign of circumcision, and so the false teachers were likely appealing to that to tell the churches of Galatia that they needed to be circumcised to be counted as the children of Abraham and so be included in the inheritance of eternal life. Paul’s already pointed out numerous problems with that teaching, but here he points out another: Abraham didn’t just have one child. He had two.


To take you back to the Abraham story, by age 75 Abraham was childless. Some of you wish to have children but remain single; that can start to cause grief as early as your 20s. Imagine being 75! And Abraham was not even single; many assume that if they could get just get married, they’d have kids, but those who have struggled with infertility know that’s not the case. Abraham was married, but his wife, Sarah, was infertile. Infertility is another incredibly difficult circumstance emotionally for those who desire children; imagine being 75 and feeling like it’s definitely never going to happen. This was especially the case in the ancient world, where a person’s worth and value was tied very closely to having children. But God came to Abraham at 75 and promised Abraham not only that he would have a child, but that God would make from him a great nation, and through this great nation, all the families of the earth would be blessed.


So Abraham believes God’s promise. But then a decade passes, and still he and Sarah have no child. So they decide to take matters into their own hands. Instead of walking by faith in God’s promise, they acted on what their eyes saw: They saw a woman who had been infertile her whole life, who was now in her 80s, and then they also saw a young, apparently fertile slave of theirs named Hagar. So they decided that Abraham should have a child with Hagar, and sure enough, that’s what happened. His first son was with Hagar, and he was named Ishmael. But then, another decade later, God fulfilled his promise and gave post-menopausal, in-her-nineties Sarah a child named Isaac, and eventually we learn that it was Isaac who God named Abraham’s heir, not Ishmael.


What was the difference between the two children? The first that Paul focuses on in verse 23 is that one was the product of human effort, “born according to the flesh” as he says there, while the other was the product of God’s effort in fulfilling his promise. And that right there is the contrast between the law and the Christian gospel. The law tells you what you must do, and those who live under the law say, “Ok; I’ll do it.” But the gospel tells us what God has done in Christ, and therefore extends to us a promise: Whoever believes in Christ will not perish but have eternal life. Those who live under it do not say, “Ok; I’ll do it.” Instead, they say, “Ok; I see now that I can’t do it, but that Christ did it for me. I’ll believe it.”


It is the law, then, that comes naturally to the flesh. Circumcision is an especially vivid picture of that: In it, you literally do something to your flesh, and the false teachers were saying that’s what was necessary for someone to be a child of Abraham and an heir of eternal life. Their teaching was so deceptive because it is so intuitive to the flesh. What do people always say when you tell them salvation is by faith alone in Christ alone? “What so you mean we don’t have to do anything? That can’t be.” Walking by faith in God’s promise is actually much harder than walking by the sight of your own efforts. Remember Abraham’s scenario: Isn’t it just easier to believe he could have a child through a young slave girl than through a post-menopausal 80-year-old who had been infertile her whole life? And isn’t it easier to believe that the good people receive eternal life than to believe that you, even with all your remaining sins, could receive eternal life through faith in God’s promise?


GEICO used to have these ads with the tagline “Saving 15% on car insurance: So easy a caveman can do it.” I once heard of a sign in front of a church that said, “Salvation: so easy a caveman can do it.” I’m guessing the church was trying to communicate that salvation was so easy that all you had to do was believe. But that’s not easy! Let me give an example: Philly is a big city for the medical field, so we always have people coming through here in various stages of medical school. I still can’t quite figure out when board exams are, which ones are the hard ones, which ones really matter and which ones aren’t as big of a deal, etc. But I know some of them at least are a big deal and that medical students typically get anxious about them and spend a ton of time studying for them. How you do on them has a major influence on your future. Now imagine someone comes to you and says, “Hey I know this board exam is a really big deal. But I don’t want you to study for it. I just want you to believe that someone already took the exam for you and got a perfect score. That score has been credited to your account. Rejoice!” What would you say? “Um, wow, ok. Can I at least see some proof of that?” “No; you just have to trust me.” “You mean you want me to pin my hopes for the future of my career on your promise?” “Yep.” Now does that sound so easy a caveman can do it? Maybe you believe them for a day, but then you start to feel anxious the next day: “Ugh; I know I don’t know everything I need to know for that exam. What if the promise isn’t true? I better get my books out.”


That’s what the churches of Galatia were doing! They were saying, “I’m not so sure about this whole promise thing. We better get circumcised.” And so we are prone to this too. We hear God’s promise that whoever believes has eternal life, but we don’t feel like we have eternal life. We see the remaining sin in our lives and we don’t feel righteous in God’s sight. So what do we do? We look to our flesh. We say, “Ok; I can’t rejoice yet. I have to first grow in my evangelism, in my care for the poor, and I have to totally eliminate that one sin from my life before I can rejoice, then, once I can look at my record of righteousness and see that it is complete, I’ll rejoice.” The problem with that, though, is that it’s never complete. You go share the gospel so you can stop feeling guilty about your lack of evangelism, and you feel better…for a day or two. But then you realize something else you aren’t doing, and you have to go do that.


We do this in less religious ways too. Throughout this series we’ve been saying that if you aren’t trying to be justified in God’s sight, you will still try to be justified in someone’s sight, and you’ll inevitably rely on the flesh to do so. It’s amazing how often getting married and having children is still, thousands of years after Abraham and Sarah, one of the most common ways to do this. Many people still feel like if they hit their late 30s or maybe 40s and remain unmarried without children that there is something defective about them. They don’t feel righteous in other words, and so what does the flesh do? It cooks up a plan: I’ll marry someone who’s not a Christian even though I’m a Christian, I’ll enter or stay in an unhealthy relationship because it seems like my only shot at marriage and children, I’ll try to have children outside of marriage because it seems like marriage isn’t happening. Think about the massive power today of psychological techniques, diets, exercise, and so forth. These things are not all bad, but why do they have such power over us? Why do we rely on them, live on the lookout for the next one, and get dejected when we don’t measure up to the one we’re on? It’s because they are ways for us to feel righteous by our flesh, by our own efforts, and the flesh prefers that to setting all its hopes for the future on a promise. There are two ways to live, represented by Abraham’s children: You can set your hopes for the future on your efforts, or you can set your hopes for the future on God’s promise of eternal life to all who believe in Christ. The law corresponds to the first, the gospel to the second, and we see next that you don’t want to take the law option, because the law produces slavery, while the gospel produces freedom.


The law produces slavery, the gospel produces freedom


So Paul says in verse 24 that the story of Abraham’s two children can be interpreted allegorically. There is a deeper meaning to the story than meets the eye, and this is often the case in the Bible. Let me just give a word of caution here: When you read the Bible, you should not be thinking first and foremost about how to find that “deeper meaning.” If you try to read the whole Bible allegorically, you will end up just making a lot of stuff up that is not really there. You may sound spiritual, but you’ll miss the point. Paul was able to do this because Paul knew the scriptures like the back of his hand. He had so internalized the Bible that he started to notice patterns and themes that on a first reading of a text would not occur. So in this story, he recognizes these associations: Ishmael was produced by human effort, by the flesh, while Isaac was produced by God’s effort in fulfillment of His promise. That is like two covenants, he says in verse 24. So if you want to see the deeper meaning of a text faithfully, focus on internalizing the Bible as well as Paul did. Don’t just open a passage, make it your goal to say something profound and spiritual, and then start guessing.


In verse 24 he focuses on one of these covenants, the covenant at Mount Sinai, which is the covenant with Moses, which the false teachers infecting the churches of Galatia were so fond of. Paul says this one corresponds to Hagar! The law says “do” and you will live; it operates according to human effort, and what does that sound like? The plan, by human effort, to produce a child with Hagar. And it did in fact produce another child, but what kind of child? Verse 24: Bearing children for slavery. That corresponds to the present Jerusalem, for she is in slavery with her children, verse 25. The present Jerusalem was the center of Judaism and the people of it overwhelmingly rejected Christ. It is likely even that these false teachers insisting that the churches of Galatia must keep the law of Moses came down from Jerusalem. Paul says such people may think of themselves as children of Abraham, and in a sense, as Jewish people, they are. But they are children of Abraham like Ishmael was: according to the flesh, and still enslaved.


The law given through Moses, which they were still living under, was given to a people who had just been released from slavery in Egypt, but what it did was expose and reinforce a deeper slavery. It showed the people of Israel what God required, and therefore exposed the many ways they fell short of it. It was like an X-ray machine, exposing that there was something deeper wrong with them: Though they were free from Egypt, they were still slaves of sin. But the law itself provided no remedy for that. It had a sacrificial system to point to the need for sacrifice, but the blood of bulls and goats could never take away sin, and though it told them what they ought to be and do, it could not make them into who they ought to be, or give them the desires necessary to do what they ought to do. It’s like telling someone who hates their job that they still must do it, and they must do it perfectly to get paid. That’s enslaving.


On the other hand, the people of the other covenant belong not to the Jerusalem that now is, but the Jerusalem above. In Hebrews 11 we read that when Abraham received the promise of an inheritance, he went out from his homeland looking for a city whose maker and builder was God. We read there that he desired a better country, that is, a heavenly one. The promise to Abraham was not ultimately that he would inherit the present Jerusalem, but the Jerusalem that is above, a heavenly city. The citizens of that Jerusalem above are free, and continuing the allegory, that Jerusalem is our mother, not the present Jerusalem.


What, then, does it mean that we are free? It means a lot, but one aspect pertinent to this passage is described in The Westminster Confession of Faith 20.2. There the confession reads: “God alone is Lord of the conscience, and hath left it free from the doctrines and commandments of men which are in any thing contrary to His Word, or beside it in matters of faith or worship.” In other words, the freedom of the Jerusalem above consists in the freedom to not do anything contrary to God’s Word, or beside it in matters of faith or worship. So if anyone tells you you must worship false gods, you are free to not do so, though they may declare you wicked. You don’t have to be justified in their sight! You are justified in God’s sight. AND, not only are you free from the doctrines and commandments of men which are contrary to God’s Word, you’re free from those that are additional to it in matters of faith or worship. So circumcision, in the context of Galatians, is not contrary to God’s Word (God doesn’t forbid it), but it is additional to it, and even from that, then, the churches of Galatia were free, though the false teachers would call them wicked for not doing it. Paul says you don’t have to be justified in their sight, because you are justified in God’s sight.


And when you live by faith in God’s promise, you will feel this freedom. Live by the law, and you never will. Live by the law, and you will never know you’re doing good enough. So when you hear others saying, “You know you need to do ______,” you’ll feel like, “Dang. Maybe I do. What if that’s the one thing I lack?” So let’s run through a few examples using a test I would encourage you to use any time you feel pressure to do anything. Ask: Is this something God actually requires of me in his Word? Our world today pressures us to feel like we must affirm things contrary to God’s Word. Is that something God requires in his Word? Clearly not; in fact it is contrary to what God requires. Therefore, you are free from it. You are already justified in God’s eyes; you don’t have to be justified in the world’s eyes. Maybe that’s an easy example; let’s try this test on some others. Your family explicitly pressures you to get married, or you just feel the peer pressure of seeing your friends get married and have kids while you remain single. Does God actually require that you get married? I think it’s fair to say that the Bible directs you to pursue marriage and having kids if you do not have the gift of singleness, but you can’t actually just go make marriage happen, and you are even free to choose not to marry if you can do so without excessive temptation to sexual sin and you are doing so to use your singleness for greater service in Christ’s kingdom. Once again, you are free!


Consider evangelism, which we’ve been talking about a good bit in our church lately. Sometimes Christians really do use guilt to motivate one another to evangelize. Or, here’s what I find more commonly: I hear a story of someone else’s evangelism, or another church’s evangelism, that really ought to encourage me, and instead, it makes me say, “Oh crap; I ought to be doing more of that. What’s wrong with me?” If that’s your response to the work of God in the lives of others, it’s almost a guarantee that you are living under the law. You still feel like you need to measure up to be righteous in God’s sight, and that other person makes you worry that you aren’t measuring up. Do you see the slavery? Ok, so what does God actually require? He does require that I give an answer for the hope that is in me. If I never talk to those who don’t believe about the gospel, something is wrong. But the Bible never tells me exactly how that has to look. In other words, God doesn’t require that you do exactly what that person who just shared about their awesome evangelism does. It doesn’t say anything about the frequency with which you must do it. It just says be ready to do it. So you’re free to rejoice in the ways others are doing it, without feeling like you must do it the same way. And here’s the cool part: That kind of joy, that kind of freedom, will, in the long run, make you a better evangelist.


And here’s another cool part: Even when you do come across things God actually requires like evangelism, you are free from needing to do it for your justification. You don’t need to wait until you do it to rejoice. You aren’t waiting until you do what God requires to become a child of the Jerusalem that is above. She is your mother now, and so you are free to rejoice the moment you are born again into her family. You are a citizen of heaven, a child of Abraham, and a child of God the moment you believe. So even when you feel pressed to do something God truly does require, don’t let it make you feel like any less of a citizen of heaven or a child of God. Believe the gospel then, and then, as a free child of God, do what your Father wants you to do. The law produces slavery, but the gospel produces that kind of freedom.


And finally, you don’t want to live under the law because those of the law are your enemies, not your friends.


Those of the law are your enemies, not your friends


Ok, so now bringing home the allegory, Paul says in verse 28 that the churches of Galatia are, in this allegory, like Isaac, the child of the promise. But then look at how he who was born according to the flesh persecuted him who was born according to the Spirit. Actually, before you do that, notice how Paul can interchange being born of the promise and being born of the Spirit. The contrast to the flesh, what we can do by our own efforts, is the promise, what God does by His effort, and what God does by his effort, he does by His Spirit. Throughout this passage we see these two ways to live: On the one hand, there is the law, our flesh, human effort, slavery, and the present Jerusalem; on the other hand, there is the gospel, the promise, the Holy Spirit, freedom, and the Jerusalem that is above. And here Paul points out how those of the one way treat those of the other way.


At that time Ishmael, the child born according to the flesh, persecuted Isaac, the child born according to the promise. Paul says that’s what’s happening now! In Jerusalem it was happening, and the book of Acts in particular records that history: The unbelieving Jews there especially persecuted the Jews who believed in Christ, along with the Gentiles who believed in Christ. So these false teachers tell you to be circumcised? They aren’t your friends! They’re doing what the children of the flesh have always done to the children of the promise: They’re harassing them!


Today we commonly assume that persecution comes from the unbelieving world, but within the Bible and throughout the history of the church, it’s often those who appear to be believers, who have some fleshly connection to us, or who may even profess to be Christians, who persecute those who are born according to the Spirit. In the early church it was the Jews claiming to be the people of God who persecuted their fellow Jews who were born of the Spirit. Tomorrow is Reformation Day, where we remember the day that Martin Luther first called for a disputation with the Roman Catholic hierarchy of his day in 1517, an event which by no intention of his own, sparked the Protestant Reformation. I’d be remiss, therefore, not to mention how Luther and his brethren were persecuted by the Roman Catholic hierarchy, professing Christians, who relying on their efforts to merit eternal life, violently persecuted those born of the Spirit in their day. And so today, how often is it the case when one is truly converted that they find their professing Christian family, or even perhaps the church in which they grew up, telling them not to be so zealous about it all?


So what does Paul tell us to do in response? Verse 30: Cast out the slave woman and her son, for the son of the slave woman shall not inherit with the son of the free woman. For the churches of Galatia, the application of this was obvious: Cast out those false teachers! Don’t give them a slot in your worship gatherings, don’t listen to their sermons, don’t invite them over to share their thoughts when you meet in your homes, don’t financially support them, and so on. It doesn’t seem that they were members of the churches of Galatia, but if they were, this would be a clear call to excommunicate them, which is just a word the Church has historically used to refer to removing someone from the membership of the church.


And so if we have people in our church who are persistently telling the people of our church that they must do things God has not required of them, that is grounds for church discipline. There is a biblical process for that, and we outline it more in our baptism and membership class: You go to the person individually, you take one or two others, you tell the church, and only then, if they refuse to repent, do you excommunicate them. But we must be willing to do that. You may think, “It’s ok; it’s not affecting me,” but 1.) How do you know that? False teaching is deceptive, as is your own sin nature. The scripture in verse 30 doesn’t say, “Keep the slave woman and her son around as long as you don’t feel too bothered by them.” It says “Cast them out!” and 2.) Even if you could be confident it wasn’t affecting you, a little leaven leavens the whole lump, as we’ll see Paul say in chapter 5. You need to think not just of yourself, but of your weaker brothers and sisters. The freedom we have as children of the Jerusalem that is above is precious, and easily hindered when people hear over and over again that they must do things God has not required. So we must be willing to cast out those who persist in doing so by removing them from our membership. And we must be willing to do similar things even with those who aren’t members of our church, as it seems was the case with these false teachers in Galatia. We can’t remove people from something they’ve never joined, but we can say to them, “Hey, we aren’t going to give you a platform to keep hurting people. You cannot come to this Citygroup,” for example.


But beyond what we must do with those who persist in such false teaching, notice the seriousness with which we must take infringements on true Christian freedom. That’s the kind of vigilance we all must have with Satan’s efforts to rob us of our freedom in Christ. Cast out the thoughts that you must do things God has not required in his word! Cast out the thoughts that you must do all things written in God’s word before you can rejoice in what Christ has done for you! Jesus is the ultimate child of the promise, who was born, not only of a post-menopausal woman, but of a virgin! He did all that the law required, suffered its curse in our place, and then the Spirit gave him new life, not from a dead womb, as in Isaac’s case, but from death itself in a dead tomb, all in fulfillment of God’s promise. If you’ve not yet believed in him, give up your efforts to be justified by your efforts, whether you are trying to be justified in God’s sight, or in the sight of others. It will only leave you enslaved. Believe in Christ, though, and the moment you do, you are declared a citizen of the Jerusalem that is above, and you share in its freedom. You are free from the doctrines and commandments of people in anything contrary to God’s word, or additional to it in matters of faith or worship, and you are free even from the demand to obey God’s word in order to be justified. Cast out any thoughts to the contrary. Don’t obey whatever you feel pressure to do in order to feel accepted by God or anyone else. Believe that you have been accepted by God by faith alone in Christ alone, and then, out of the freedom that brings, obey what God does actually require, as a son obeys the father he loves.