The real children of Abraham, then, are those who put their faith in God.

God gave the promises to Abraham and his child. And notice that the Scripture doesn’t say “to his children,” as if it meant many descendants. Rather, it says “to his child”—and that, of course, means Christ.

God’s Children through Faith

Before the way of faith in Christ was available to us, we were placed under guard by the law. We were kept in protective custody, so to speak, until the way of faith was revealed.

For you are all children of God through faith in Christ Jesus.

And now that you belong to Christ, you are the true children of Abraham. You are his heirs, and God’s promise to Abraham belongs to you.

Think of it this way. If a father dies and leaves an inheritance for his young children, those children are not much better off than slaves until they grow up, even though they actually own everything their father had.

And that’s the way it was with us before Christ came. We were like children; we were slaves to the basic spiritual principles of this world.

God sent him to buy freedom for us who were slaves to the law, so that he could adopt us as his very own children.

And because we are his children, God has sent the Spirit of his Son into our hearts, prompting us to call out, “Abba, Father.”

Oh, my dear children! I feel as if I’m going through labor pains for you again, and they will continue until Christ is fully developed in your lives.

Abraham’s Two Children

Tell me, you who want to live under the law, do you know what the law actually says?

And now Jerusalem is just like Mount Sinai in Arabia, because she and her children live in slavery to the law.

As Isaiah said, “Rejoice, O childless woman, you who have never given birth! Break into a joyful shout, you who have never been in labor! For the desolate woman now has more children than the woman who lives with her husband!”

And you, dear brothers and sisters, are children of the promise, just like Isaac.

So, dear brothers and sisters, we are not children of the slave woman; we are children of the free woman.