Living by Promise, Not by the Law

In Galatians 4:21–31, Paul makes a really interesting point about the difference between living under the Law and living under God’s promise. He’s writing to the Galatians because some of them were starting to think they needed to follow the Law—like circumcision and other rules—to be right with God. Paul pushes back on that and basically says: if you really understood the Law, you’d realize it was never meant to save you in the first place¹.

To explain this, Paul goes back to Abraham. Abraham had two sons—one with Hagar, a slave woman, and one with Sarah, a free woman². Ishmael (Hagar’s son) was born the natural way—through human effort and planning. But Isaac (Sarah’s son) was born through God’s promise, even when it seemed impossible³. That’s the key difference Paul is pointing to: one represents human effort, the other represents God stepping in and doing what only He can do.

Paul then says this story is more than history—it’s an allegory⁴. Hagar represents Mount Sinai and the Law, which leads to slavery. Sarah represents the “Jerusalem above,” which stands for freedom and God’s promise⁵. In other words, trying to earn your way to God through rules puts you in bondage, but trusting in God’s promise brings freedom.

He also points out that Ishmael mocked and persecuted Isaac⁶, just like people who rely on works often push back against those who live by faith. Then Paul brings it home by quoting Scripture: Hagar and her son were sent away because Ishmael wouldn’t share in Isaac’s inheritance⁷. The message is clear—what comes from human effort can’t inherit what comes from God’s promise.

Paul wraps it up simply: we are not children of the slave woman, but of the free woman⁸. That means as believers, we don’t depend on rules or religious systems to save us. We depend on God’s grace.

The big takeaway is this: the Law has a purpose—it shows us our need for God—but it was never meant to save us⁹. Salvation comes through trusting God’s promise, fulfilled in Jesus Christ. Just like Isaac was the child of promise, we are too. So instead of trying to earn our way to God, we live in the freedom that comes from faith in Him.

Footnotes

¹ Galatians 4:21

² Galatians 4:22; Genesis 16–21

³ Galatians 4:23; Hebrews 11:11

⁴ Galatians 4:24

⁵ Galatians 4:25–26

⁶ Galatians 4:29; Genesis 21:9

⁷ Galatians 4:30; Genesis 21:10

⁸ Galatians 4:31

⁹ Romans 3:20; Galatians 3:24