Passage: Isaiah 54 (with Galatians 4:21-31)
The Big Idea
In Galatians 4, Paul quotes the first verse of Isaiah 54, the way a good teacher points students to a passage to study later. When we follow him there, we find a chapter overflowing with promises. Our spiritual life is not sourced from ourselves. It is a free gift from God to His beloved children.
How Do We Do God’s Will?
Step number one: read and believe this sentence.
Christians are not under the Law (Romans 6:14).
This is where the stones start flying and people line up for the debate. So I will say it again. Christians are not under the Law. Did you see that period?
Why do so many Christians, including many pastors, seem to want to go back under the Law every day? It is like we are searching for the one rule that will finally bring freedom, the one thing we can do that will finally work.
Paul’s Question (Galatians 4:21)
Paul asks the Galatians: you who want to live under the law, do you even know what it says?
They had been convinced to leave the gospel of grace for law-based religion. They wanted to be measured by God’s perfect standard, and yet they had no idea what it really demanded. They had a low view of the Law, and an inflated view of themselves. We call that pride: “I’m a good person. Let me give it my all and see what happens.”
Many also carry a “karma” view of life: you get what you give, you get what you deserve. That does not fit the New Covenant of grace at all.
Two Ways to Live Every Day
This is really about how we do God’s will daily.
By the flesh. If I choose the flesh, I must try my best to keep the Law. There is no other option. Everything is sourced by my own strength, desire and ability. Every day I have to try harder, give more, or walk away. This path always leads to frustration and burnout. Eventually I start to believe the gospel doesn’t work for my problems, and I am driven toward despair.
By the Spirit. This is walking in the truth and freedom Jesus promised. The Law doesn’t cease to exist; we simply are not bound to it anymore.
Does that mean our lives will abound with sin? No. The opposite. When Jesus and His Spirit are our focus, sin becomes an afterthought. We may still sin, but fellowship with Jesus, His very life in us, rips sin up by the root. We discover we don’t really want to sin anymore. The Law declares how short we fall. Jesus speaks forgiveness and mercy.
Two Sons, Two Covenants (Galatians 4:22-31)
God promised Abraham and Sarah a son in their old age. That was impossible. So Abraham had a choice: trust God for a miracle, or try to make God’s will happen through his own effort.
He chose both at different times.
- Hagar and Ishmael represent Mount Sinai and the Law. Ishmael was born by human effort trying to bring about God’s promise. Even living in his father’s house, he was the son of a slave (Galatians 4:23-25).
- Sarah and Isaac represent the heavenly Jerusalem. Isaac was born when Sarah finally believed God. He was the product of a miracle, and he lived free (Galatians 4:26).
Abraham and Sarah were probably trying to do God’s will through Hagar. That is the point. Our flesh can never produce the life God intends. We cannot have Isaac by our own effort.
Here is a simple test: Am I making promises to God? Or am I looking to His promises in faith?
Paul adds that those born of the flesh always persecute those born of the Spirit (Galatians 4:29). People who choose law often struggle to accept the freedom of those who live by grace. They cannot imagine a life that doesn’t depend on them.
The Promises of Isaiah 54
If we are supposed to live by God’s promises, we need to know what they are.
Isaiah 54:1. Fruit from barrenness. God promises to bless the desolate, childless woman with more children than the one who seemed fruitful. Spiritual fruit does not come from where we naturally expect. If you have struggled to bear fruit, His grace is for you. Our response is to sing.
Isaiah 54:2-3. Enlarge your tent. This is a call to act in faith and expect His promises to come true. He promises so much fruit you will burst at the seams, because He knows the power of His Son’s life in you.
Isaiah 54:4. No more shame. Shame and disgrace are dissolved in the New Covenant. He says it twice. The day is coming when you won’t even remember it. You can live without fear of regretting your life.
Isaiah 54:5. Your Maker is your Husband. God promises the faithfulness and love of a husband. His power and willingness to rescue are the foundation of the relationship. He made you, and He bought you back.
Isaiah 54:6. He meets us in devastation. He calls back the grieving, abandoned wife. He dives into the places where no one else could do anything.
Isaiah 54:7-8. Everlasting compassion. The real separation sin caused is more than overcome by the grace of Jesus. He is not angry with you. He has great compassion for you.
Isaiah 54:9. A promise like Noah’s. Just as He swore never to flood the earth again, He swears never again to be angry with His people or punish them. Even when I act foolishly, His promise stands. Every time I see a dry earth, I can remember it.
Isaiah 54:10. Unshakable love. Mountains may move and hills disappear, but His faithful love and covenant of peace will never be removed. That is how the New Covenant works.
Isaiah 54:11-12. Rebuilt with jewels. My value used to be based on my weak performance. Now God rebuilds me with gifts: sapphire foundations, ruby towers, gates of gems. My life is defined by His work, not my failure.
Isaiah 54:13. Peace for your children. God decides the legacy of your life. What He does through you will be a solid rock for those connected to you.
Isaiah 54:14-17. No weapon will prosper. God is for you. Trials are part of a larger plan to bless you (Romans 8:28). Every accusing voice will be silenced. Your vindication comes from Him. Just as Jesus was not destroyed, even by death, you will live to the glory of God your Savior.
Grace Takeaway
What is God’s will in all of this? For us to believe these great and precious promises (2 Peter 1:4). We don’t have to earn this life, and we don’t have to maintain it. We live as promise believers, not promise makers.