The woman's seed -- or offspring -- in this case seems to point forward not to all humanity but to the one specific human sent by God to deal with the issue of sin that is now loose in the world. There is indeed enmity between Jesus and the snake, or Satan. They work at cross-purposes and are diametrically opposed to each other. Jesus sums this up in John 10 -- using the metaphor of a shepherd and his sheep, Jesus refers to the thief -- not a far leap to read Satan into that -- and says that the thief comes to steal, kill and destroy. Then he adds of himself, "I came that they might have life, and have it abundantly."
So the snake -- Satan -- is out to steal the life God gives, to kill those whom God has made alive, to destroy all the abundance Jesus longs to create in us. Jesus comes to give us life, life abundant. These two are enemies.
How will it turn out? We've seen this enmity down through the ages. Cain and Abel, Isaac and Ishmael, Jacob and Esau, Joseph and his brothers, Moses and Pharaoh -- down through the ages enmity continues between people. Sometimes it's clear who is on the side of the serpent and who serves God; most of the time it seems the conflict plays into the serpent's desires and a God-given peace is all-too-elusive.
But God's words to the snake point to an ending. "You shall bruise his heel" sounds like a wound, but a non-lethal wound. "He shall bruise" -- or crush -- "your head" -- now that is a problem for the serpent.
At the beginning of his movie The Passion of the Christ, Mel Gibson portrays Jesus in the garden of Gethsemane in dialogue with Satan. Actually Satan keeps speaking to Jesus, and Jesus keeps speaking to his Father, which is pretty good insight. But while Jesus stands talking to the Father, Satan shifts forms and becomes a snake slithering around Jesus' feet. After he has prayed, "Not my will but thine be done," Jesus stomps on the head of the serpent. Not a bad picture of the relationship between the two. Certainly a nod to this verse.
So far we've been talking about this as though it was all happening (as Bishop Usher calculated it out) in 4004 B.C. Back then. But I've been maintaining all along that this is our story. So?
So ... how badly we need to hear this word, at this point! When we are caught in sin, when we are blaming each other, when we are anticipating the heavy hammer of God's judgment falling on our heads, we hear this word. It is not a word of condemnation, but a word of hope. "He shall crush your head," sounds like we may someday be free from the bondage to sin, Satan, and death. Right now we live behind fig leaves, laying our shamed heads on our heavy hearts each night, but someday will come -- someday when the serpent is destroyed, when the seed of the woman will conquer the powers of hell.
One of the classic explanations -- "atonement theories" they're called -- of exactly what happens at the cross is called the "Christus Victor" theory. It says that at the cross, Christ won a victory over the powers of sin, death, and hell. Having won a battle against the powers that enslave us, Jesus set us free to enjoy the life -- abundant life -- that he gives. We have been liberated, set free. Yes, we still live with old wounds. Yes, we have a long ways to go. But we no longer live in bondage to that scaly serpent and his lies. The son of the woman has set us free.