The Mother Promise
Covenant Theology 101 (#5)
Covenant Breakers and the Covenant Keeper.
When a child first learns to ride a bike, a parent promises, “I’ll be right here. I won’t let go.” The child, wobbly and afraid, trusts that voice behind them. The parent, then, has to let go. The child falls, skin scraped, and pride bruised. Through tears, they look back expecting anger—but instead see the same voice walking toward them with open arms: “Get up. Let’s try again.”
That’s what grace looks like in action. The promise of love comes first; the fall exposes weakness; yet the same promise meets us again, stronger than before. Genesis 3:15—called the mother promise—is God’s “I’ll be right here.” Humanity fell hard, but the promise of redemption was already chasing us down. From that moment, all of Scripture unfolds as God’s story of picking up his fallen children and fulfilling his word, no matter the cost.
Covenant theology helps us understand how God reveals himself throughout the story of Scripture. We should want to read our Bibles the way God intended them to be read. And studying how God’s covenants all fit together helps us read all the diverse parts of Scripture as parts of the one unified story.
In the Garden, God entered into a relationship with Adam in the form of a covenant. The covenant law was that if he ate of the tree of the knowledge of good and evil, he would die—implying that if he were obedient, he would live. This is why we called it the “covenant of works.” The life Adam would receive would be eternal and heavenly in the presence of his Creator.
When Adam broke that covenant, God entered into another kind of relationship with Adam, Eve, and ultimately us—the covenant of grace. The Westminster Confession says: “Man, by his fall, having made himself incapable of life by that covenant, the Lord was pleased to make a second, commonly called the covenant of grace” (7.3). One of the proofs offered is Genesis 3:15. In the midst of judgment upon the serpent, the Lord made a promise: “I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel.” This verse is called the mother promise because from it all of God’s gracious work of saving sinners is given birth.
Continuing Covenant Theology 101, let’s explore this mother promise.
Its Context: Judgment
The judgment context of this promise reminds us that we can’t understand rightly God’s grace unless we first understand our guilt. The covenant threat was, “In the day you eat of [the tree of knowledge] you shall surely die.” Adam broke that law because he chose his own desires instead of the Lord’s. That’s why John said, “sin is lawlessness” (1 John 3:4).
Then came the judgment. “And they heard the sound of the Lord God walking in the garden in the cool of the day, and the man and his wife hid themselves from the presence of the Lord God among the trees of the garden” (Gen. 3:8). When a child hears the sound of their parent’s footsteps coming near to their room, how do they feel? Are those footsteps happy or sad? It depends on what they’ve done. If they just woke up in the morning, it might be the happy sound that breakfast is ready; but if they’re hiding, that sound brings dread. The word “sound” is used in Old Testament contexts to communicate the sound of approaching hoofbeats. But these are the sound of the Lord’s coming. And they hid because they knew it was judgment time!
Its Content: Grace
Yet in this moment of judgment, God didn’t close the book on humanity. The covenant threat was death, but they didn’t die—at least physically. Why? Grace. “Mercy triumphs over judgment” (Jas. 2:13).
Note the shift between the covenant of works and the covenant of grace highlighted in the pronouns. In the covenant of works God says, “You shall…” (2:17); in the covenant of grace, he says, “I will…” (3:15). The covenant of works rested on Adam’s obedience; the covenant of grace rests on God’s gracious desire to save sinners. Think of that child hearing their parents’ footsteps after disobedience. The door opens, and the child expects punishment—instead, the parent kneels down and says, “I forgive you.” The mother promise is like that, but infinitely better!
God promises to bring redemption through conflict—“I will put enmity” between the serpent and the woman, between their offspring. This war will end with victory: “He shall bruise your head, and you shall bruise his heel.” Adam should have crushed the serpent’s head. The Lord promises to do it himself.
But how can he be so gracious after threatening death? Because he is both just and the justifier of the one who has faith in his promise to come (Rom. 3:26). God did not set aside his justice but satisfied it. He sacrifices an animal in the place of Adam and Eve, then covered them with its skin as a sacramental sign of a sacrifice to come. What a gracious God!
Stuttgart Psalter (ca. 820-830) on Psalm 91:13
Its Climax: Jesus
What did that first sacrifice point to? To the day when the promised offspring would come: “He shall bruise your head,and you shall bruise his heel.” The Lord would bring this war to its climax in the battle between the true Serpent—Satan—and the Son of God, the second Adam, Jesus Christ. Jesus triumphed, bruising Satan’s head even as his own heel was wounded on the cross. This was prophetic of Jesus’ cross and crown, his death on the tree of the cross and his resurrection from the tomb. “Now is the judgment of this world; now will the ruler of this world be cast out” (John 12:31). On the cross, “God made [us] alive together with him…canceling the record of debt that stood against us…He disarmed the rulers and authorities and put them to open shame” (Col. 2:13–15). By his death, Jesus “destroyed the one who has the power of death, that is, the devil” (Heb. 2:14).
Yet we still wait for the final fulfillment. The serpent still writhes, sin still tempts, but his doom is certain. There is an already aspect to Christ’s victory, but also a not yet fully seen aspect. Jesus has already trampled Satan’s head; what is not yet is our trampling: “The God of peace will soon crush Satan under your feet” (Rom. 16:20).
Covenant Breakers and the Covenant Keeper
Behind everything you read in Scripture stands this mother promise. For covenant breakers like us, it is the seed of hope and the spine of redemption. Every covenant that follows—the promise to Noah, Abraham, Moses, and David—grows out of this one. From Genesis to Revelation, all the triumphs and especially all the failures of God’s people point forward to the coming Covenant Keeper—who still says to his fallen children, “I’ll be right here.”