The dragon had first entered the story in Revelation 12:3. That fearsome dragon can now finally be exposed for who he really is because now he is thoroughly defeated and tossed aside—to the greater glory of the Victor. His names direct our attention to the Lord’s promise to the serpent immediately after his victory in the Garden: 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
(Genesis 3:15). His being thrown out of heaven demonstrates that the Lord God has bruised (or crushed) the serpent’s (seven) head(s); the Lord has kept his promise! This is glorious gospel for the woman and her offspring!
9 And the great dragon was thrown down, that ancient serpent, who is called the devil and Satan, the deceiver of the whole world he was thrown down to the earth, and his angels were thrown down with him.