Two Mothers; Two Sons; Two Covenants; Two Cities Part 2 (Galatians 4:28-31) 

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Two Mothers, Two Sons, Two Covenants, Two Cities–

to which of Each Two Do You Belong? Are you Free? part 2

Law or Grace, Galatians 4:21 to 5:1, part 2–4:28 to 5:1

South Africa, January 17, 1934–Chuck Swindoll shares the story. An impoverished diamond prospector named Jacobus Jonker, discouraged by his string of bad luck, decides to stay home on this particularly cold and windy day. The night before, torrents of heavy rain washed away loads of silt from his fruitless claim of land, and this morning he’s in no mood to sort through the flotsam and jetsam left behind. Instead, he sends his son Gert and some hired hands to work the land.

Later that day, Jacobus hears a ruckus on the road and sees Gert speeding home like a madman, abruptly parking his vehicle and leaping from its seat. Something bad must have happened. Had somebody been hurt? Killed? But rather than a look of panic, Gert wears a smile from ear to ear. As Jacobus opens his mouth to scold his son for his reckless driving, Gert places an egg-sized stone in his hand.

Despite its rough state, the 726-carat diamond glistens in the daylight. Suddenly, Jacobus’s legs give out. With tear-filled eyes, he falls to his knees, thanking God for the miraculous find that would make him and his seven children wealthy beyond imagination. The diamond would yield well over five million dollars–in 1934. They were set for life–or were they? The true story of the famous Jonker Diamond, however, doesn’t end in perpetual fame and fortune. Instead, within a few years, Jacobus Jonker again found himself penniless–having mismanaged his funds, Jonker found himself once again combing the earth, hoping to find another treasure that would restore his fortune.

A fortune lost, a treasure squandered, a priceless gem wasted. Our world is full of fascinating stories of men and women who suddenly strike it rich, only to lose all their friends, family, fame and fortune within months. Well, the Christians in Galatia were no different. When Paul and Barnabas preached the Gospel of Jesus Christ to them, they received that priceless gift of salvation by grace through faith, with no strings attached. Yet within months, they had allowed these ruthless swindlers to plunder their faith.

The legalistic false teachers called Judaizers sought to rewrite the Galatians’ glorious riches of grace, by replacing them with a pitiful religion of works. They tricked the Galatians into traditions–getting circumcised, attending festivals and becoming Jews first to be saved. In the midst of the Judaizers’ winning converts to their legalistic cause, Paul’s letter to the Galatians arrives, like a skilled general come to retake his homeland.

Now as chapter 4 closes, Paul finalizes his exposure of the Judaizer false beliefs, while re-establishing the clear truth of justification by grace through faith in Christ alone. Last week in verses 21 to 27, Paul gives a profound illustration comparing salvation by faith using free Sarah, her son Isaac, and heavenly Jerusalem with salvation by works, using Hagar the slave, Ishmael and Mount Sinai along with present Jerusalem.

What’s the setting for these verses? Verses 21 to 31–Paul just returned from his first missionary journey. It took place primarily in modern day Turkey, in the Galatian region of the New Testament. Paul preached the Gospel of salvation by grace alone, through faith alone in Christ alone, because of His crucifixion and resurrection alone. People responded and churches were formed.

But shortly after his return to his basecamp in Antioch, false teachers from Jerusalem arrived and began teaching the Gentile believers they must become Jews in practice first before they can be saved. The false teachers wanted to add the Mosaic Law to the promise made to Abraham, where Abraham was reckoned righteous before God by faith. Some of the Galatians bought into the lie–some got circumcised, others sought to keep the Law to earn their way to Heaven and lost their spiritual freedom.

So to persuade the Galatians they were free from the Law, free in Christ, free to obey the Word, free from earning approval from God–Paul opens with . . .


Look at verse 21. Sarcastically, Paul begins with a pointed question, “Tell me, you who want to be under law, do you not listen to the law?” In other words, “So you want to be under the Law, do you? Well, do you realize the Law itself tells you not to be under the Law?” So Paul uses a true, historical situation to illustrate the difference between grace and Law.


Read verses 22 to 23, “For it is written that Abraham had two sons, one by the bondwoman and one by the free woman. 23But the son by the bondwoman was born according to the flesh, and the son by the free woman through the promise.” These two wives and two sons illustrate the difference between obeying the Law and depending on God’s grace in order to be saved. According to the flesh means Ishmael’s birth was motivated by Abraham and Sarah’s lack of faith in God’s promise, and fulfilled by sinful, human means. Abraham did this his own way, on his own–like a works salvation.

But through the promise means God miraculously enabled Abraham and Sarah to have Isaac when Sarah was well past childbearing age and had been barren her entire life. God was the one who provided this child–God did the work and Abraham depended. The bondwoman illustrates a religion of human achievement and the free-woman illustrates a faith in divine accomplishment. The wrong religion is you trying to earn it. The right faith is you trusting God to provide it. But to really make his point, Paul uses . . .


Look at verses 24 to 27. Paul uses an argument style the rabbis and false teachers used, yet Paul is unique here–Paul uses real, historical people and real places from the Old Testament. Verses 24 to 27, “This is allegorically speaking, for these women are two covenants: one proceeding from Mount Sinai bearing children who are to be slaves; she is Hagar. 25Now this Hagar is Mount Sinai in Arabia and corresponds to the present Jerusalem, for she is in slavery with her children. 26But the Jerusalem above is free; she is our mother. 27For it is written, ‘Rejoice, barren woman who does not bear; break forth and shout, you who are not in labor; for more numerous are the children of the desolate than of the one who has a husband.’” Paul compares the two systems—slavery to freedom

Hagar–a slave woman                                                 to Sarah–a free woman

Ishmael–born according to the flesh                            to Isaac–born through God’s promise

Mosaic covenant of Law, based on works                    to covenant of promise, based on faith      

Present Jerusalem–Judaism                                        to Jerusalem above–those in Christ

Children of present Jerusalem—Legalists                    to Children of Jerusalem above being Lovers

Righteousness by LAW                                               to Righteousness by FAITH

Paul is slamming the door on anyone who wants to add works to grace or faith. So Paul now concludes this illustration with some practical application for today. Read aloud with me verses 4:28 to 5:1, “And you brethren, like Isaac, are children of promise. 29But as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so it is now also. 30But what does the Scripture say? ‘Cast out the bondwoman and her son, for the son of the bondwoman shall not be an heir with the son of the free woman.’ 31So then, brethren, we are not children of a bondwoman, but of the free woman. 5:1It was for freedom that Christ set us free; therefore keep standing firm and do not be subject again to a yoke of slavery.”

#4  THE PRACTICAL APPLICATION  Verses 28 to 31 and 5:1

There are two mothers (Hagar and Sarah), two sons (Ishmael and Isaac), two covenants (old and new), and two cities (the “now” and “new” Jerusalems). The question Paul now asks is this—to which of these two groups do you belong? The reason this matters is–to be a true child of Abraham is to be a son or daughter of God, which is the greatest privilege in the world. But it is not enough to claim Abraham as our father, as the Judaizers did, because Abraham had two sons, and only one of them was free.

F. F. Bruce says, “If you insist on the priority in the inheritance of Abraham’s descendants according to the flesh … remember this: Abraham indeed had a son according to the flesh, of whom it is expressly stated that he was not to share the inheritance.” Therefore, the crucial question becomes, “Who is your mother?”

First  Are you a child of PROMISE?

Verse 28, “And you brethren, like Isaac, are children of promise.” Paul’s point is, those who have begun to sink back into the trap of legalistic Judaism must remember they are children of promise. The Galatians, and you all today, owe your new life not to their own effort, but to the miraculous power of God–just as Isaac did in the physical realm. Paul wants the Galatians to see that by the promise of God (not Law and not works), they are free sons and daughters of Sarah.

You get it, right? Here it’s not, “Who’s your daddy?” but, “Who’s your mommy?” Do you recall what the promise was? It is the promise God first gave to Abraham, that all the nations of the world would be blessed through him. In other words, it is the promise of the Gospel, the promise of the coming Christ, the promise of justification by grace alone through faith alone–the promise God gave to Abraham that he was reckoned righteous by faith.

According to that promise, all it takes to be a child of God is to believe by faith that Jesus died on the cross for our sins and rose again from the dead. God’s gracious, sovereign power gave them life–so now to fall back under Law was to deny God’s divine work and dishonor Him. And here, did you notice what Paul called those who were tempted to compromise their faith? Verse 28, “And you brethren”–Paul calls the Galatians “brothers” because they were the children of that promise. God’s promise to Abraham is not simply for Jews as Jews. Rather, God’s promise is for every believer, whether Jew or Gentile.

Do you remember Galatians 3:26, ”In Christ Jesus you are all sons of God, through faith.” Galatians 3:29, “If you are Christ’s, then you are Abraham’s offspring, heirs according to promise.” The ones who truly belong to Abraham are the ones who belong to Christ. Anyone who has faith in Jesus is God’s true child in the line of Isaac–born again and made free by the promise of God.

Christian brothers and sisters, when you live each day forgetting all the promises God has blessed you with, how much grace you have been given, that your salvation had nothing to do with your efforts, and that your relationship with Christ now and your future in Heaven with Him was given to you by faith–you will slowly, subtly slide back into a religion of works, efforts, Law-keeping, and empty ritual. You will show up to church without any thought of Jesus. You’ll participate in ministry without any thought of who you are serving. Paul tells you to remember you are a child of God’s promises–for when that is real, then you can ask . . .

Second  Are You PERSECUTED?  Verse 29

The people who are trying to be saved by works, scale from suspicion to anger toward those who are saved by faith. Works religion folks don’t like grace faith folks–and that’s the way it has been from the very beginning with the two sons of Abraham. Verse 29, “But as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so it is now also.”

Paul teaches, the spiritual descendants of Isaac, who are born according to the Spirit, can still expect persecution from the spiritual descendants of Ishmael, “who was born according to the flesh.” Even when they were children, Ishmael resented, mocked and laughed at Isaac. When Abraham held a feast to celebrate Isaac’s weaning, Ishmael mocked the occasion. At that event in Genesis 21:9, “Now Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, mocking.” Seventeen-year-old Ishmael was not merely teasing his little half-brother–he was treating him with contempt. Ishmael hated Isaac, just like his mother Hagar hated Sarah. Although they were born fourteen years apart, the two siblings were rivals.

Notice Paul’s additional phrase at the end of verse 29, “so it is now also.” Paul teaches the Galatians–throughout history, and still today, the physical and spiritual descendants of Hagar and Ishmael have, respectfully oppose to openly persecute the physical and spiritual descendants of Sarah and Isaac. Have you ever heard the phrase, “tensions in the Middle East”? This is where it all began–right here with Ishmael and Isaac. It’s Abraham’s fault–when he tried to fulfill God’s promise his way, not God’s way.

And in the same way, those who hold to a salvation by works, trusting in their own performance of the Law, hate those who proclaim salvation by grace without works. The Judaizers thought of themselves as the legitimate, God-honored descendants of Abraham through Isaac–but what Paul says here infuriates them. Because of their religion of self-effort salvation, in reality they are the descendants of Ishmael and Hagar–and this is what is driving the tensions in the Galatian churches.

By writing verse 29, “So also it is now,” Paul is teaching Christians that they should expect exactly the same kind of treatment Isaac received from his big brother. Whether within Judaism or Christianity, legalists have always been persecutors. Those who trust in God have always been persecuted by those who trust in themselves. True believers have always been more mistreated and oppressed by religionists than by atheists. Even in the future, it is the false religious system of Revelation 17:6 that is “drunk with the blood of the saints.”

It is false religion that does the persecuting. So whenever people who claim to be religious start to oppress minorities, hate Jews, or attack homosexuals, we can be sure they do not represent true Christianity–even if they do it in the name of Jesus. The most serious persecution often comes from the people who claim to be religious.

And persecution is one way to tell the difference between true and false religion. Persecution is the opposition Christians face for speaking or doing God’s will. Persecution can include ridicule, loss, violence, and even martyrdom. One of the distinguishing marks of real Christians is that they are willing to suffer persecution for their faith, and even to die for it. Second Timothy 3:12, “Indeed, all who desire to live godly in Christ Jesus will be persecuted.”

Persecution was happening in Galatia–the sons of Hagar were persecuting the sons of Sarah, Jews were persecuting Christians, and the Gentiles who came to faith in Christ were being oppressed by the Judaizers, who would not let them live by God’s free grace. If what you really want is to be liked, then you’ll never make a very good Christian. An unwillingness to suffer should cause you to wonder about your faith. Martin Luther said, “If someone does not want to endure persecution from Ishmael, let him not claim that he is Christian.” Are you a committed Christian or merely a convenient Christian?

Third  Are You INHERITING?  Verse 30

What makes this life, filled with suffering and persecution, more than tolerable is what awaits you in the future. The spiritual children of Sarah and Isaac will receive an inheritance that the spiritual children of Hagar and Ishmael will not. Verse 30, “But what does the Scripture say? ‘Cast out the bondwoman and her son, for the son of the bondwoman shall not be an heir with the son of the free woman.’”

Are you in God’s heavenly family? Ishmael never received his Father’s inheritance, even though Abraham asked God to give it to him in Genesis 17. God blessed Ishmael in many ways, but not with the promise of salvation by faith. Finally, when tensions rose, in Genesis 21 Sarah said to Abraham to “cast out the slave woman and her son,” and God told Abraham this was right, for Isaac was to receive the inheritance.

The inheritance comes to those who depend on the Lord, not on the Law. The inheritance comes to those who come God’s way (Isaac) not man’s way (Ishmael). The inheritance is given to those who come by faith, not by works. And the inheritance changes everything in how you live today.

One reason Christians are willing to be disliked, even persecuted for their faith, is that they know what God has in store for them. We are God’s children, and our heavenly Father has promised us an eternal inheritance of infinite delight. God’s family, identified in local churches, is united under similar doctrine and direction. When there is active, defiant opposition to that doctrine and direction, the Church doesn’t function like a democracy, but a monarchy–and Christ our King plainly teaches verse 30, “Cast out the bondwoman and her son.”

Paul is quoting Genesis 21:10 to illustrate that those who are attempting to be justified on the basis of keeping the Law will be cast out of God’s presence forever. This is a repeated reality in the Scripture. Matthew 22:12 and 13, “’Friend, how did you come in here without wedding clothes?’ And the man was speechless. 13Then the king said to the servants, ‘Bind him hand and foot, and throw him into the outer darkness; in that place there will be weeping and gnashing of teeth.’”

By Paul quoting Sarah’s words in verse 30, he’s teaching in a not-too-subtle way, that the Galatians needed to drive the Judaizers and their legalism right out of the church. By trying to place Gentiles under the Law, the false teachers proved they themselves were actually slaves, spiritually speaking, and therefore had no part in God’s inheritance. Because salvation is by grace, then the Church cannot tolerate salvation by works. Freedom in Christ can be preserved only by abolishing any and all bondage to the Law.

Romans 16:17, “Now I urge you, brethren, keep your eye on those who cause dissensions and hindrances contrary to the teaching which you learned, and turn away from them.” Titus 3:10, “Reject a factious man after a first and second warning.” You and I must stand firm against salvation by works and pay any price to preserve salvation by faith alone. The persecutors will be thrown out, and the persecuted will receive their promised inheritance.

As Sarah had Hagar and Ishmael cast out of Abraham’s household in Genesis 21, so will their unbelieving descendants, those who live by works of the flesh, those who live by the law, those who try to earn their own salvation, be cast out of God’s household. Matthew 7:22 and 23, “Many will say to Me on that day, ‘Lord, Lord, did we not prophesy in Your name, and in Your name cast out demons, and in Your name perform many miracles?’ 23And then I will declare to them, ‘I never knew you; depart from Me, you who practice lawlessness.’”

God still works today the way He worked with Hagar and Sarah. Salvation comes by grace and not by works. Righteousness comes through faith and not through the Law. Christianity is not a list of “dos and don’ts.” Christianity is God doing the work to rescue you from judgment over your sins that comes by faith alone. Christianity is a relationship with Christ, where you are in Christ and Christ is in you. This is why you cannot be saved through any other religion except Christianity.

The other religions–like Judaism, Hinduism, Islam, and Mormonism–are all slave religions. The same may even be said of versions of Christianity, like Roman Catholicism and liberal Protestantism–they add works to faith as the basis for our righteousness before God. They make you a slave and bring you under bondage, because they are about what you do for God (that never ends and is never good enough)–not about what God has done for us in Jesus Christ. Leading Paul to ask . . .

Fourth  Are you LIVING FREE?  Verse 31

What God has done in Jesus Christ is offer His free salvation to all who trust in Him. Martin Luther explained it like this–“Those who try to achieve the status of sons and heirs by the righteousness of the Law or by their own righteousness are slaves, who will never receive the inheritance even though they work themselves to death with their great effort; for they are trying, contrary to the will of God, to achieve by their own works what God wants to grant to believers by sheer grace for Christ’s sake.”

If you’re working to gain God’s acceptance, you must realize you’re still a spiritual slave. If you want to be free, you need to ask God for the gift of his grace. Then you will be able to join with all His sons and daughters in saying, verse 31, “So then, brethren, we are not children of a bondwoman, but of the free woman.”

Even though believers are (verse 31) “brethren in Jesus Christ and therefore not children of a bondwoman, but of the free woman,” they are nevertheless under obligation to live faithfully for their Lord. Chapter 5:1, “It was for freedom that Christ set us free; therefore keep standing firm and do not be subject again to a yoke of slavery.”

In light of what Paul’s been teaching throughout this letter, he implies a disturbing question here. “Why, then, do some of you want to go back to being like Ishmael, who was a slave, an outcast, and separated from God?” It made no sense at all. Christians have been made free. We don’t have to earn our salvation–and now as born again believers, we have a new heart that wants to serve Christ.

But thanks be to God” Paul shouts to the Romans in 6:17 to 19, “that though you were slaves of sin, you became obedient from the heart to that form of teaching to which you were committed, 18and having been freed from sin, you became slaves of righteousness. 19I am speaking in human terms because of the weakness of your flesh. For just as you presented your members as slaves to impurity and to lawlessness, resulting in further lawlessness, so now present your members as slaves to righteousness, resulting in sanctification.”

Paul teaches emphatically, that God’s stated purpose for our salvation, our redemption, was for the freedom of the believer. Christ set us free from the “guilt-establishing and deadening power of the law” through His death and resurrection. That’s why going back into a yoke of slavery is absurd. Yet the believers in Galatia were being duped by the Judaizers to consider doing just that.

The spiritual descendants of Sarah and Isaac should live as they had been living, by faith. The encouragement command is to “keep standing firm”–and the warning command is literally “do not subject yourselves again” so that all believers will persevere in freedom. Like an animal loosed from pulling a plow, we should not seek to be hooked up again.

On a personal level, Galatians 4:21 to 5:1 continues to contrast the way of the Judaizers and the way of Paul–the way of works and the way of faith. But on the most important level, doctrine, this passage has been an extended series of contrasts between the way of Law and the way of grace, the way of works and the way of faith, the way of man and the way of God.

Following that same pattern, you also explicitly or implicitly see the contrasts of Hagar and Sarah, Ishmael and Isaac, children of Satan and children of God, Law and promise, wrath and mercy, bondage and freedom, Old Covenant and New Covenant, Sinai and Zion, present Jerusalem and Jerusalem above, fleshly and spiritual, rejection and inheritance, and lostness and salvation.

The point is clear–there are only two ways to live. One is self-dependence and the other is Christ-dependence. To live trusting in human accomplishment or trusting in divine achievement–the way of Satan or the way of Christ, God’s way or your way. Paul says to choose one or the other. Do not vacillate between the two.

Take Home

A  Christian, enjoy your FREEDOM found in Christ

You can sing, “It is well with my soul.” My sin, O the bliss of this glorious thought, my sin, not in part, but the whole is nailed to the cross, and I bear it no more, Praise the Lord, praise the Lord, O my soul!”

You have been saved from the penalty of sin and the power of sin—and one day you will be delivered from the very presence of sin. And in Christ, you’ve been made free to love, you’ve been made free to obey God’s commandments, you’ve been made free with a new nature that wants to please Christ from your very heart. Yes, confess your sin. Yes, repent of your sin. Yes, get help with your sin from others. But also enjoy the bliss of forgiveness of all your sin and the power to live above it. Enjoy your freedom found in Christ.

B  Christian, have you been PERSECUTED?

Persecution is not when 1) your boss tells you to turn down your Newsboys music, 2) they run out of glutton free communion cups, 3) you worked four weeks in a row as a children’s substitute and no one said, “Thanks”, 4) you are the only Christian family in your neighborhood, 5) no one buys your worship album or buys your book or your Christian candles, 6) when you miss your team’s kick-off because the service ran a little long.

No–persecution is ridicule, loss, violence, and even martyrdom because of Christ, His Word and especially His Gospel message of salvation by grace, through faith in Christ alone. Second Timothy 3:12, “Indeed, all who desire to live godly in Christ Jesus will be persecuted.” Have you been persecuted–and if not, ask why not?

C  Church attender, HELL is a place you don’t want to go!

In the 1600’s Puritan Ralph Venning quotes and comments on Matthew 25:41, “Then He will also say to those on His left, ‘Depart from Me, accursed ones, into the eternal fire which has been prepared for the devil and his angels.’” Heed this warning as Pastor Venning expands and explains this single verse.

“It is as if sinners should say to God in the day of judgment, ‘Lord have mercy upon us!’ ‘Have mercy upon you!’ says God. ‘No, I will have no mercy on you. There was a time when you might have had mercy without judgment, but now you will have judgment without mercy. Depart! Depart!’

…If they should then beg and say, ‘Lord, if we must depart, let it be from YOUR throne of judgment, but not from YOU.’ ‘No,’ says the Lord, ‘depart from me; depart from my presence in which is joy. Depart and go to Hell.’

“…‘Lord,’ they say, ‘seeing we must be gone, bless us before we go so that YOUR blessing may be upon us.’ ‘Oh no,’ says God, ‘go with a curse; depart, YOU accursed.’

‘Oh Lord, if we must go from YOU, let us not go into the place of torment, but appoint some place, if not of pleasure, then of ease.’ ‘No, depart into fire, burning and tormenting flames.’

“…‘Oh Lord, if into fire, let it be only for a little while; let the fire soon be out or us soon out of it, for who can dwell in everlasting burnings?’

‘No, neither you nor the fire shall know an end; be gone into everlasting fire.’

‘Lord, then let it be long before we go there.’ ‘No, depart immediately; the sentence shall be immediately put in execution.’

…‘Ah! Lord! let us at least have good company who will FEEL SORRY FOR us even though they cannot help us.’ ‘No, you shall have NO ONE but tormenting devils; those whom you obeyed when they were tempters you shall be with as tormentors.’ What misery sin has brought on man! to bring him to hear this dreadful doom!”

Christ says, “Come to me, and I will give you rest,” or, “Depart from me accursed ones.” You can cry out to Christ to open your heart and save you this very day. Let’s pray.

About Chris Mueller

Chris is the teaching pastor at Faith Bible Church - Murrieta.

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