1 Samuel 17:8-11
Goliath stood and shouted to the ranks of Israel, "Why do you come out and line up for battle? Am I not a Philistine, and are you not the servants of Saul? Choose a man and have him come down to me. If he is able to fight and kill me, we will become your subjects; but if I overcome him and kill him, you will become our subjects and serve us." Then the Philistine said, "This day I defy the ranks of Israel! Give me a man and let us fight each other." On hearing the Philistine's words, Saul and all the Israelites were dismayed and terrified.
Wouldn’t Goliath have been furious if he had known he was prophesying about Israel’s Deliverer?  “Choose a man and have him come down to me. If he is able to fight and kill me, we will become your subjects; but if I overcome him and kill him, you will become our subjects and serve us."  When David fought and killed Goliath, it was an example of Christ’s future battle on the cross with Satan.  

With the covering of Christ’s death and resurrection in our lives, we no longer are slaves to sin.  Because of Christ’s righteousness, Satan no longer has the right to accuse or malign us.  Instead, we have authority over him; the very enemy that enslaved us is now in servitude to us.  The rights that Adam and Eve lost when they sinned were restored through Christ.
Jesus said, “I will give you the keys of the kingdom of heaven; whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven.”             ( HYPERLINK "http://www.biblegateway.com/passage/?book_id=47&chapter=16&verse=19&version=31&context=verse" Matthew 16:19)
Amen!!  Lord help us to live as Victors.