Children of a New Covenant
Galatians 4:21–31; 9/20/2026; Brother Mike Lei
Good morning. My message today is “Children of a New Covenant.” We will be looking at Galatians 4:21–31. We will be talking about three points today:
- The Two Covenants — verses 21–26
- Rejoice in Desolation — verse 27
- Cast Out the Slave Woman — verses 28–31
Let’s pray before we begin.
The Two Covenants
Galatians 4:21–26
Let’s read verses 21–26 together.
21 Tell me, you who desire to be under the law, do you not listen to the law? 22 For it is written that Abraham had two sons, one by a slave woman and one by a free woman. 23 But the son of the slave was born according to the flesh, while the son of the free woman was born through promise. 24 Now this may be interpreted allegorically: these women are two covenants. One is from Mount Sinai, bearing children for slavery; she is Hagar. 25 Now Hagar is Mount Sinai in Arabia; she corresponds to the present Jerusalem, for she is in slavery with her children. 26 But the Jerusalem above is free, and she is our mother.
Hagar represents the Old Covenant, and Sarah represents the New Covenant. Hagar was a slave, but she had a son, Ishmael, with Abraham first. Sarah was Hagar’s master, but fourteen years later, she had a son, Isaac, with Abraham. Abraham was eighty-six years old when Hagar gave birth to Ishmael, according to Genesis 16:16. Abraham was one hundred years old when Sarah gave birth to Isaac, according to Genesis 21:5. So, what is the difference between the two covenants?
The Old Covenant was a covenant established by God with the Israelites. God chose them out of the nations to have a special covenant relationship with Him. Through Abraham, Isaac, and Jacob, God multiplied their descendants into a great nation and gave them the Promised Land, Canaan, as their possession. The Israelites were to worship God alone and obey His laws. If the Israelites were faithful to keep the covenant, God promised to bless them according to the blessings of the covenant. If they were unfaithful to the covenant, God promised to punish them according to the curses of the covenant. Under the covenant, God established a sacrificial system and appointed priests to represent the people before Him and offer sacrifices to cover their sins. But the nation of Israel as a whole was not faithful to keep the covenant.
They worshiped other gods, set up idols, practiced wickedness, and came under the judgment of God according to the covenant. Then God promised to give them a New Covenant.
Jeremiah 31:31–34 says: 31 “Behold, the days are coming, declares the Lord, when I will make a new covenant with the house of Israel and the house of Judah, 32 not like the covenant that I made with their fathers on the day when I took them by the hand to bring them out of the land of Egypt, my covenant that they broke, though I was their husband, declares the Lord. 33 For this is the covenant that I will make with the house of Israel after those days, declares the Lord: I will put my law within them, and I will write it on their hearts. And I will be their God, and they shall be my people. 34 And no longer shall each one teach his neighbor and each his brother, saying, ‘Know the Lord,’ for they shall all know me, from the least of them to the greatest, declares the Lord. For I will forgive their iniquity, and I will remember their sin no more.”
God says that there will be a day when He will make a New Covenant with Israel and Judah. He will put His law within them and write it on their hearts. He will be their God, and they will be His people. They will know God personally. This is what happens in the New Covenant. This promise, originally given to Israel and Judah, has also come to the Gentiles through the grace of our Lord Jesus Christ. When both Jews and Gentiles receive Jesus Christ as Lord and Savior, the Holy Spirit comes to dwell within us. We hear the voice of the Holy Spirit speaking to us, primarily through the Word of God in the Bible. We then become children of the New Covenant. So, what does it mean to have a new heart?
I was reading the biography of Rev. Paul Chang, who served with the Christian National Evangelism Commission in Southeast Asia. In the book, his daughter talked about her parents. She said: “When I was eleven or so, I decided that church was boring. I didn’t want to go. I wanted to stay home and watch the good TV shows on Sunday morning. I reasoned that I could believe in God even if I didn’t go to church. I told my mom and dad that I didn’t want to go. My parents didn’t scold me, persuade me, or give me a lecture. They simply said that I could do what I wanted to do. But they gave me one condition: after a month, I had to ask myself whether this was the right thing to do and whether it was helping me know God. I agreed. I thought it would be fun.I watched TV for four hours straight the first Sunday. The next Sunday, I did the same thing, but halfway through, I got sick of it. On the third Sunday, I went back to church. I knew that putting television in the place of God was meaningless and boring.” This is a picture of what it looks like when God gives us a new heart under the New Covenant. We have new desires for the things of God. The things of the world no longer appeal to us in the same way. We become tired of the things that used to tempt us. We lose interest in things we used to enjoy because we realize that they are not pleasing to God. For example, we may stop using bad language or saying hurtful things. But we need to continue walking by faith and in obedience with this new heart that God has given us. This new heart needs to be cultivated through continual obedience to God’s will. Don’t stop seeking to obey God in everything.
Have you started following Jesus Christ after becoming a Christian, but slowly lost your zeal to obey God in everything? The New Covenant sets us free to live for God by the power of the Holy Spirit. We are no longer trying to earn God’s favor; we are enjoying God’s favor. We are no longer trying to earn God’s love; we are enjoying God’s love. We are no longer trying to earn God’s salvation; we are enjoying the fruits of salvation. We are no longer trying to obey God because we are afraid of punishment; we obey God because of the joy given by the Holy Spirit.
Hebrews 10:35–36 says: 35 Therefore do not throw away your confidence, which has a great reward. 36 For you have need of endurance, so that when you have done the will of God you may receive what is promised. You need to run the race with endurance in order to receive the great reward God has promised. Don’t give up. Don’t slow down. Don’t get sidetracked.
Hebrews 11 reminds us of the heroes of faith who came before the New Covenant—people like Abel, Enoch, Noah, and Abraham. And it tells us that God has prepared something better for us. Now you have something better than what they had. You have the New Covenant. Your life of faith should be even more amazing because you have the New Covenant. Do you believe that?
Rejoice in Desolation
Galatians 4:27
verse 27 says: “Rejoice, O barren one who does not bear; break forth and cry aloud, you who are not in labor! For the children of the desolate one will be more than those of the one who has a husband.” Paul is quoting from Isaiah 54:1.In Isaiah, God is speaking to the barren city of Jerusalem, where almost no one was left because many had been taken captive or had perished at the hands of the Babylonians. God was promising that the heavenly Jerusalem would give birth to more children than the earthly Jerusalem. We are the children God is talking about. When Jesus returned to heaven, there were only about 120 disciples gathered in the upper room in Jerusalem. On the day of Pentecost, after Peter preached his first sermon, about 3,000 people were added to the church. By around AD 350, it is estimated that there were approximately 30 million Christians.
In 2015, Christians remained the largest religious group in the world, making up nearly one-third, or about 31 percent, of the world’s population of 7.3 billion people. A report from the Center for the Study of Global Christianity at Gordon-Conwell Theological Seminary estimated that there would be approximately 2.6 billion Christians worldwide by the middle of 2023 and around 3.3 billion by 2050. This is truly a cause for rejoicing when we look at the amazing growth of Christianity from the beginning, after Jesus returned to heaven. Let us praise the Lord for this growth! Amen?
The word “rejoice” in verse 27 means to celebrate, to be merry, to feast. This is like how we should be during the holidays. We should be in a joyful and festive mood, right? Why do we feel this way? Why do we automatically become joyful and festive during the holidays? It is because something good is happening. First of all, we get time off from school and work. That is already a reason to celebrate. But more than that, holidays usually have a reason for celebration. At Christmas, we celebrate the birth of Christ. At Thanksgiving, we celebrate God’s goodness. As Christians, we should be in a festive mood every day when we think about all the blessings we have in the Lord. We can celebrate our new life. We can celebrate the blessings we have in Christ. We can celebrate the salvation of people who come to Christ. Even in desolation, we can rejoice. “For the children of the desolate one will be more than those of the one who has a husband.” Why? Because we walk by faith, not by sight. Our eyes are looking toward the things in heaven, where our treasures are, rather than focusing on the things of the earth, where we will always see brokenness.
Cast Out the Slave Woman
Galatians 4:28–31
Verses 28–31 say: 28 Now you, brothers, like Isaac, are children of promise. 29 But just as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so also it is now. 30 But what does the Scripture say? “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.” 31 So, brothers, we are not children of the slave but of the free woman.
What does the “slave woman and her son” represent? The slave woman and her son represent whatever causes trouble and hinders Christians from following the Lord. So, get rid of anything that keeps you from enjoying the freedom you have in Christ, including those sins that enslave you. Don’t let the world pressure you to conform to its ways. Be like Isaac! Isaac was separated from bad influences, represented here by Hagar and Ishmael, so that he could grow into the man of God who would carry on God’s promise to Abraham. How can we be like Isaac, the child of promise? Do you remember what the name Isaac means? It means “laughter.”
Be people of laughter—people who live by faith in the Lord and are not burdened by fear and worry.Someone from the Southern Baptist Convention Executive Committee once wrote:“Laughter is your birthright, a natural part of life that is innate and inborn. Infants begin smiling during the first weeks of life and laugh aloud within months of being born.” He also wrote: “Begin by setting aside special times to seek out humor and laughter, as you might with exercise, and build from there.” Here are some ways to start.
1. Smile
Smiling is the beginning of laughter, and like laughter, it is contagious. Practice smiling when you look at someone or see something even mildly pleasing. Smile at the people who serve you coffee.
2. Count Your Blessings
When you hear laughter, move toward it. When you hear someone laughing, seek it out and ask, “What’s funny?”
3. Spend Time with Fun, Playful People
These are people who laugh easily—both at themselves and at life’s absurdities. They routinely find humor in everyday events.
4. Bring Humor into Conversations
Ask people: “What was the funniest thing that happened to you today?” “What was the funniest thing that happened to you this week?” “What is the funniest thing that has ever happened to you?” He writes: “Don’t go a day without laughing. Think of it like exercise or breakfast, and make a conscious effort to find something that makes you laugh each day. Set aside ten to fifteen minutes and do something that amuses you. The more you get used to laughing each day, the less effort you’ll have to make.” Brothers and sisters, let us laugh more in our lives because we are children of promise, like Isaac. Amen?
Our church should be a church that laughs a lot. Do you know why? Because our pastor and his wife laugh a lot! Practice laughing as hard as you can, even if something is only a little funny. For example: “Day 37: They still don’t suspect that I am just a cat.” Look at that cat! Haha! Someone else posted: “Day 45: I have earned the cookie’s trust. They still don’t realize I am a raisin.” Haha! And here is another one: “Day 33: They still suspect nothing.” Look, that’s a dog! Haha!
According to a study, many centenarians—people who live past the age of 100—have a positive attitude and consider laughter an essential part of their lives. The study says that these people who live to be 100 tend to prioritize peace and happiness. Their ability to find joy in life, even during difficult times, is associated with longer and happier lives. As children of the New Covenant, we can rejoice always in the Lord. Why? Because in the New Covenant, God has placed His laws in our hearts by giving us a new heart. And He has given us the Holy Spirit to dwell within us and give us the power to do God’s will. Ezekiel 36:27 promises: “And I will put my Spirit within you, and cause you to walk in my statutes and be careful to obey my rules.” Because Jesus suffered and died on the cross for our sins, we are forgiven when we trust in Him for our salvation. Our sins have been removed once and for all through the sacrifice of Jesus Christ. We can have direct and intimate access to God the Father. Brothers and sisters, let us start with a clean slate. Let us throw out the bitterness. Throw out the sadness. Throw out the anger. Throw out the disappointments. Even when things are bitter, we can rejoice. Even when things are sad, we can rejoice. Even when things make us angry, we can rejoice. Even when things are disappointing, we can rejoice. Why? Because our hope is in an amazing God who has done amazing things for us and will continue to do amazing things for His glory. Amen? Let us cast out from our lives the burdens of sadness, worry, and anxiety. For we are children of the New Covenant! We can laugh at our troubles. We can have peace and joy in the midst of difficulties. When life seems unfair, we can still smile and give praise to the Lord. The enemy wants to persecute us by bringing us down. We don’t have to give in. No matter what happens, we will have an inheritance from the Lord if we persevere.
Smile. Laugh. Be glad in the Lord!
Conclusion:
I will finish this message with the story of Adoniram and Ann Judson.
Adoniram Judson was one of the first American Protestant missionaries to Burma, which is now called Myanmar. He and his newlywed wife, Ann, committed their lives to the mission field. They were willing to go there and even prepared themselves to die there. While they were in Burma, war broke out between Burma and England. All foreigners were suspected of being spies. Adoniram was arrested and put into prison, awaiting execution. His wife, Ann, desperately tried to get him released from prison. She pleaded with the officials to free him because he was an American citizen. Eight months after Adoniram was arrested, Ann gave birth to a baby girl. After nearly a year and a half of imprisonment, Adoniram was released on the condition that he help interpret during peace negotiations with the British. He was asked to continue participating in the negotiations and had to remain away from his family. Before he could return home, he received a letter with a black seal. The letter told him that his wife, Ann, had died of fever. A few months later, their baby daughter, Maria, also died. Adoniram tried to suppress his guilt and grief, but he could not forgive himself for not being with Ann and their baby. His depression became increasingly severe. He stopped eating with the other missionaries at the mission house. Two years after Ann’s death, he went into the jungle, built a small hut, and lived by himself. He dug a grave and kept vigil there for days, filling his mind with dark thoughts about death. He said: “God is to me the Great Unknown. I believe in Him, but I find Him not.” The missionaries and native converts were concerned about him. They visited him, brought him food, and prayed for him. Slowly, he recovered from his paralyzing depression. He gained a new depth of spirituality that strengthened and intensified his ministry. His passion for the people of Burma was renewed. He remarried and continued his ministry in Burma. Sadly, his second wife also died on the mission field. He later married a third time. By the time of Judson’s death, he had translated the Bible into Burmese. There were about 100 churches in Burma and more than 8,000 believers.
Brothers and sisters, may the story of Adoniram Judson encourage you today to know that God’s promises are greater than all your troubles, sorrows, and struggles. Will you come to Him today as children of the New Covenant? Will you trust Him and claim all the promises that the New Covenant offers to you? Let us pray.
Galatians 4:21-31
21 Tell me, you who desire to be under the law, do you not listen to the law?
22 For it is written that Abraham had two sons, one by a slave woman and one by a free woman.
23 But the son of the slave was born according to the flesh, while the son of the free woman was born through promise.
24 Now this may be interpreted allegorically: these women are two covenants. One is from Mount Sinai, bearing children for slavery; she is Hagar.
25 Now Hagar is Mount Sinai in Arabia; she corresponds to the present Jerusalem, for she is in slavery with her children. 26 But the Jerusalem above is free, and she is our mother.
27 For it is written,
“Rejoice, O barren one who does not bear;
break forth and cry aloud, you who are not in labor!
For the children of the desolate one will be more
than those of the one who has a husband.”
28 Now you, brothers, like Isaac, are children of promise.
29 But just as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so also it is now.
30 But what does the Scripture say? “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.”
31 So, brothers, we are not children of the slave but of the free woman.
