Covenant Conflict and Divine Severance Text: Genesis 21:8-21
Introduction: Two Women, Two Covenants, Two Cities
Every family has its disagreements, its moments of tension and friction. But the conflict we see in the household of Abraham is no ordinary domestic squabble. This is not just a case of sibling rivalry or a dispute over the family inheritance. What we are witnessing here is a seismic event in redemptive history. It is the collision of two worlds, the clash of two principles, the visible outworking of the great division God established in the garden between the seed of the woman and the seed of the serpent. This is covenant theology played out in a tent.
The apostle Paul, under the inspiration of the Holy Spirit, tells us that this story is not just history; it is an allegory (Gal. 4:24). Hagar and Sarah are not just two women; they are two covenants. Ishmael and Isaac are not just two half-brothers; they are the progenitors of two opposing principles of relating to God. Hagar, the slave woman from Egypt, represents the covenant of works, of human effort, of fleshly striving, which was later codified at Mount Sinai. Her son, Ishmael, is the child born according to the flesh. Sarah, the free woman, represents the covenant of grace, of divine promise, of supernatural intervention. Her son, Isaac, is the child born according to the Spirit.
This is the conflict between Mount Sinai and Mount Zion, between the earthly Jerusalem which is in slavery with her children, and the heavenly Jerusalem which is free, and which is our mother. This is the conflict between legalism and grace, between self-righteousness and faith. And the central lesson of this text is that these two principles cannot coexist in the house of God. There can be no shared inheritance. The son of the flesh will always mock the son of promise, and so the son of the flesh must be cast out. This is a hard, sharp-edged truth, and it runs entirely contrary to the sentimental, inclusive spirit of our age. But it is God's truth, and it is foundational for understanding the nature of the church, the nature of salvation, and the nature of the Christian life.
This story forces us to ask a fundamental question: On what basis are we living? Are we striving to please God in our own strength, patching together a righteousness of our own making, like Ishmael? Or are we resting in the supernatural promise of God, born from above, like Isaac? The two cannot be blended. One must give way to the other. And God Himself is the one who makes the separation.
The Text
And the child grew and was weaned, and Abraham made a great feast on the day that Isaac was weaned. And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, laughing in jest. Therefore she said to Abraham, “Drive out this maidservant and her son! The son of this maidservant shall not be an heir with my son, with Isaac.” And the matter distressed Abraham greatly because of his son. So God said to Abraham, “Do not be distressed because of the boy and your maidservant; whatever Sarah tells you, listen to her voice, for through Isaac your seed shall be named. And of the son of the maidservant I will make a nation also, because he is your seed.” So Abraham rose early in the morning and took bread and a skin of water and gave them to Hagar, putting them on her shoulder, and gave her the child, and sent her away. So she went and wandered about in the wilderness of Beersheba. When the water in the skin was finished, she put the child under one of the bushes. Then she went and sat down opposite him, about a bowshot away, for she said, “Do not let me see when the child dies.” And she sat opposite him and lifted up her voice and wept. Then God heard the voice of the boy crying; and the angel of God called to Hagar from heaven and said to her, “What is the matter with you, Hagar? Do not fear, for God has heard the voice of the boy where he is. Arise, lift up the boy, and hold him by the hand, for I will make a great nation of him.” Then God opened her eyes, and she saw a well of water; and she went and filled the skin with water and gave the boy a drink. And God was with the boy, and he grew; and he lived in the wilderness and was an archer. And he lived in the wilderness of Paran, and his mother took a wife for him from the land of Egypt.
(Genesis 21:8-21 LSB)
The Mocking Laughter and the Fierce Mother (vv. 8-11)
The scene opens with a celebration, but it quickly turns sour.
"And the child grew and was weaned, and Abraham made a great feast on the day that Isaac was weaned. And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, laughing in jest." (Genesis 21:8-9)
The weaning of Isaac is a major milestone. In that culture, it likely happened when he was two or three years old. It signifies that the child has survived the most vulnerable period of infancy and that the promise is secure. Abraham throws a great feast, a public celebration of God's faithfulness. But in the midst of this covenantal joy, a discordant note is struck. Sarah sees Ishmael "laughing."
Now, the Hebrew word here is the same root as Isaac's name (yitzchaq). It can mean innocent laughter, but the context and Paul's commentary make it clear that this is not innocent fun. Paul calls it persecution (Gal. 4:29). This was the laughter of mockery, of scorn, of contempt. Ishmael, now a teenager, sees this little toddler being celebrated as the heir, and he mocks him. This is the flesh sneering at the Spirit. This is the son of human effort ridiculing the son of divine promise. It is the firstborn according to nature asserting his perceived rights against the chosen one according to grace.
Sarah's reaction is immediate and severe. She is not having any of it.
"Therefore she said to Abraham, 'Drive out this maidservant and her son! The son of this maidservant shall not be an heir with my son, with Isaac.'" (Genesis 21:10)
Modern readers, steeped in a culture of therapeutic niceness, often recoil at Sarah's harshness. But we must see this through covenantal eyes. Sarah is acting as a fierce guardian of the promise. Her demand, "Drive out this maidservant," is quoted directly by Paul in Galatians as scriptural warrant for expelling the legalists from the church (Gal. 4:30). Her maternal instinct is here sanctified and sharpened into a theological principle. She understands, perhaps more clearly than Abraham at this moment, that there can be no compromise. The line of promise must be kept pure. Ishmael cannot be a co-heir. The principle of works cannot share the inheritance with the principle of grace.
Abraham, however, is caught in the middle. His natural fatherly affection clouds his judgment. "And the matter distressed Abraham greatly because of his son" (v. 11). This is understandable. Ishmael is his son, his firstborn. The thought of sending him away into the wilderness is agonizing. But Abraham's distress shows us that our natural affections, as good as they may be, must always be subordinated to the revealed will of God. What feels right to us is not the standard. The Word of God is the standard.
The Divine Command and the Painful Obedience (vv. 12-14)
Just when the situation seems like an impossible impasse, God intervenes directly to settle the matter.
"So God said to Abraham, 'Do not be distressed because of the boy and your maidservant; whatever Sarah tells you, listen to her voice, for through Isaac your seed shall be named.'" (Genesis 21:12)
This is a stunning vindication of Sarah. God essentially says, "She's right. Do what she says." God ratifies her fierce, protective demand. This is not God capitulating to a nagging wife; this is God revealing that Sarah's words were, in fact, His own will. He clarifies the principle of election. The promise is not just to Abraham's seed in general, but to a specific, chosen line: "through Isaac your seed shall be named." This is the doctrine of election in miniature. God's purpose stands not because of human will or effort, but because of His sovereign call.
But God is not cruel. He also shows His care for Ishmael, but it is a care outside the specific covenant of redemption. "And of the son of the maidservant I will make a nation also, because he is your seed" (v. 13). This is common grace. God will bless Ishmael with earthly prosperity, with descendants, with national greatness. But he will not be the heir of the special, saving promise. This is a crucial distinction. God shows kindness to all His creatures, but His saving, covenantal love is reserved for His elect.
With God's command clarifying the issue, Abraham's duty is clear, however painful. "So Abraham rose early in the morning and took bread and a skin of water and gave them to Hagar... and sent her away" (v. 14). This is the obedience of faith. It is costly. It goes against his natural feelings. But he obeys the word of the Lord. He performs the painful surgery that God has commanded. This act of severance is necessary for the health of the covenant family.
Wilderness Despair and Divine Provision (vv. 15-19)
The scene now shifts to Hagar and Ishmael, and it is a picture of utter desolation.
"When the water in the skin was finished, she put the child under one of the bushes... she sat opposite him and lifted up her voice and wept." (Genesis 21:15-16)
This is the end of the line for human effort. The bread and water Abraham provided, the resources of the flesh, have run out. They are in the wilderness, facing certain death. Hagar's despair is total. This is a living portrait of the spiritual condition of those who are outside the covenant of promise. The resources of the flesh will always fail. The way of works always leads to the wilderness of despair and death. Left to ourselves, this is our end.
But even in the wilderness, God hears. "Then God heard the voice of the boy crying; and the angel of God called to Hagar from heaven" (v. 17). It is significant that God hears the voice of the boy. Ishmael means "God hears." Even in his exile, God is mindful of His name. The angel's words are a rebuke to Hagar's despair and a reaffirmation of God's promise. "Do not fear, for God has heard... Arise, lift up the boy... for I will make a great nation of him" (vv. 17-18).
And then comes the provision. "Then God opened her eyes, and she saw a well of water" (v. 19). Notice, God did not create a well. The well was already there. Hagar was blinded to it by her despair. This is a profound picture of God's common grace. The world is full of His provision, but we are often blind to it until He opens our eyes. This is not saving grace, but it is grace nonetheless. It is God's merciful provision for His creatures, sustaining them in this life.
The Separate Destiny (vv. 20-21)
The passage concludes with a summary of Ishmael's life, establishing his separate path.
"And God was with the boy, and he grew; and he lived in the wilderness and was an archer. And he lived in the wilderness of Paran, and his mother took a wife for him from the land of Egypt." (Genesis 21:20-21)
God's presence with Ishmael is a general, providential care. He enables him to grow and thrive in his own environment, the wilderness. He becomes an archer, a man of the wild, a man of his own strength. And his mother gets him a wife from Egypt, her own homeland. This completes the separation. Ishmael's orientation is back toward Egypt, the land of bondage, the symbol of the flesh. His destiny lies apart from the land of promise and the people of the covenant. He will become a great nation, as God promised, but it will be a nation of the flesh, forever set in opposition to the nation of promise.
Conclusion: Cast Out the Bondwoman
So what does this ancient family drama have to do with us? Everything. As Paul teaches in Galatians, this is our story. The church is the household of Abraham. And within the visible church, there have always been two kinds of people: Ishmaels and Isaacs. There are those who are members by fleshly descent or outward conformity, who rely on their own works, their own morality, their own religious performance. They are sons of the bondwoman, slavery to the law. And there are those who are members by supernatural birth, who rely solely on the promise of God in Christ. They are sons of the free woman, born of the Spirit.
And the son of the flesh will always, always mock the son of promise. The legalist will always despise the one who rests in grace alone. The self-righteous will always persecute the one who boasts only in the righteousness of Christ. This conflict is inevitable. And the command of Scripture is just as sharp and uncompromising today as it was in Sarah's mouth: "Cast out the bondwoman and her son, for the son of the bondwoman shall not be heir with the son of the free woman" (Gal. 4:30).
This means, first, that we must cast this principle out of our own hearts. We must ruthlessly expel any reliance on our own efforts for our standing with God. We are not saved by faith plus our good intentions. We are not saved by faith plus our religious activity. We are saved by grace alone, through faith alone, in Christ alone. We are Isaacs, children of promise, born not of the will of the flesh but of God.
Second, this means the church must maintain the purity of the gospel. When the teaching of legalism, the doctrine of Ishmael, begins to mock the children of promise, it must be driven out. We cannot make peace with a gospel of works. We cannot allow the inheritance to be shared. The gospel of grace is the central treasure of the house of God, and like Sarah, we must be fierce in its defense.
The separation is painful. Abraham was greatly distressed. But it is a necessary and God-ordained surgery. For the promise to go forward, the flesh must be cut away. Let us therefore rejoice that we are children of the free woman, not of the slave. Let us stand firm in the liberty with which Christ has made us free, and never again submit to a yoke of slavery.