God’s Word for You – Galatians 4:21-23 The Two Sons

GOD’S WORD FOR YOU
GALATIANS 4:21-23

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21 Tell me, you who want to be under the law, don’t you hear the law? 22 For it is written that Abraham had two sons, one by the slave woman and one by the free woman. 23 His son by the slave woman was born according to flesh; but his son by the free woman was born through a promise.

I think that Luther is right about this point of the letter. Paul had wanted to finish the document with what he had just written about wishing he were with them now (verse 20). But then it occurred to him that people will often learn from a good example, a story, rather than just accurate words in a logical order.

So Paul introduces his “allegory” here. Theologians and students of the Bible will recognize this as the one and only allegory of the entire Bible, if “allegory” it is, and we will talk more about this word when it occurs in verse 24. But to begin with he makes his whole point in these three verses without any application yet.

To begin with, Paul calls Moses’ first book “the law.” This is remarkable to us, since we recognize that Moses’ other four books, Exodus, Leviticus, Numbers and Deuteronomy, preach the law much more; dramatically more. In Genesis, what law is there? There was the law about the tree in the garden, and there was the law about circumcision, and there was the simple moral law about loving God and loving each other which we see violated by the rampant sins of the wild and lawless people who were annihilated in the great flood (Genesis 6:5,11-12). But all of that accounts for about six or ten verses out of fifty chapters. But the Jews and the early Christian church were in the habit of calling all of Moses “the law.” Jesus himself did this in his preaching (Matthew 5:17; 7:12; 11:13; John 1:17; 7:19; 12:34).

It is in this law that we learn about Abraham and his two sons. These things are recorded in Genesis, among the many tumultuous things that happened between the years when Abraham was eighty-six and one hundred (Genesis 16 through 21).

Sarah, at 75 or 76, had not given birth to any children for Abraham. God had spoken of descendants in large numbers, like the stars in the sky (Genesis 15:5,13,18), and it was Abraham’s faith in this promise in particular that God credited as righteousness (Genesis 15:6). Sarah decided to take matters into her own hands and gave a slave girl that she had, Hagar, to her husband as a concubine. Perhaps this girl could give her husband a son. But Hagar, who may have been a mere teenager, began to despise Sarah when her belly soon began to swell. For this, Sarah beat the girl and caused her to run away. But the Lord himself, as the Angel of the Lord (the first appearance of this title in the Scriptures) met her and encouraged her. It is clear from Genesis 16:15 that Hagar returned to the family and that she was received back into their tent. Following this came the covenant of circumcision (chapter 17) when Abraham was 99 and Sarah was 89. Then, in the visit God made to Abraham just before Sodom was destroyed, the Lord promised that Sarah herself would have a son. All of this would have been known to the Galatians from their regular weekly worship (Acts 14:1), so Paul only has to mention a couple of details to make his point: A son of the slave woman and a son of the free woman. The slave woman’s son was born “according to flesh,” which of course means that he was a son brought about in the natural way. He was a son of Abraham, and an heir of Abraham. But then Isaac was born, whose mother Sarah had never been a slave. She was a free woman, the daughter of Terah. God did not promise anything to do with Ishmael, the slave woman’s son, before Hagar conceived him. But long before Sarah conceived Isaac, God had promised that he would be the son that they were waiting for, and he even promised his name ahead of time (Genesis 17:19). Luther’s insight is brilliant on this fact: “No one but Paul has ever observed this difference, which he gathered this way on the basis of the text of Genesis” (LW 26:434).

Paul draws a conclusion based on Genesis 21:12: “Your descendants will be named through Isaac.” Abraham’s line through Ishmael is not the line of Israel, even though they are a physical line of descent. But Abraham’s line through Isaac is the line that comes on account of the promise. As Paul also says in Romans: “It is not the natural children who are God’s children, but it is the children of the promise who are regarded as Abraham’s offspring” (Romans 9:7). So Ishmael was born like all other children, more or less by chance, with the mother uncertain ahead of time whether or not she will get pregnant, or how often. She only chooses a husband whom she and her parents think will be a good man and a good provider for her. But Sarah had a promise, a certainty, which was also a prophecy from God’s own mouth: “Your descendants will be named through Isaac.”

This point could take us one of two ways: Either the Judaizers are right, and the only thing that matters is continuing to be brought under the covenant of circumcision to become heir just as all of Israel’s descendants were heirs. Or else this whole account, which was about the spiritual descent through Abraham, isn’t about the flesh at all, but about something else, which is the word of God and the promises of God. Are God’s people counted as such on account of the flesh, regardless of faith at all, or on account of faith, regardless of flesh? If we are God’s people on account of the flesh with no regard for faith, then why did the rebellions of Korah and Dathan meet with opposition from God? Why were kings like Ahab and the two Jeroboams condemned by God’s prophets? Why did Judas Iscariot fall into despair? Weren’t all of those men circumcised Israelite men, descended physically from Abraham? Of course they were. But salvation is not a matter of the flesh, for God looks at the heart (1 Samuel 16:7).

In Christ,
Pastor Timothy Smith

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Pastor Smith serves St. Paul’s Lutheran Church, New Ulm, Minnesota
God’s Word for You – Galatians 4:21-23 The Two Sons

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