When the seventy-two return from their mission they are full of joy. Their stated reason is because “even the demons are subject to us in your name!” Jesus affirms they are correct. What does Jesus mean when he says, “I saw Satan fall like lightning from heaven”? For Satan to fall from heaven is for him to experience a defeat. His not being in the heavens curtails his power over peoples and nations. That it happens like lightning indicates the speed and finality of what has occurred.
But what has caused this fall and defeat? As the seventy-two preach, they preach about the approach of the kingdom of God. This accompanied by people being turned toward God and also by powerful acts (including the driving out of demons). Literally, the kingdom’s advance comes with the defeat and driving out of the darkness. This the preaching of the gospel is the cause of Satan’s power being curtailed.
Jesus affirms this when he says, “Behold, I have given you authority to tread on serpents and scorpions, and over all the power of the enemy, and nothing shall hurt you.” This recalls the promise in Genesis how the seed of the woman would crush with his heel the serpent’s head. While this refers to Jesus, as the seed of Eve, it now applies also to those children of Eve who are united with this son of man. Consequently, Satan’s defeat means that he has no authority or power to harm us. And even should he bruise our heel and we experience death, still we remain unhurt and live with Christ.
Notice that Jesus says it is not the driving out of demons that should excite us but rather that our names are written in heaven – we are his and preserved to continue in Christ. This is a source of greater joy.