Overcoming

Excerpt from John Piper's response to "Do you believe we should cast out demons today?"

That text from Revelation 12:11—"They overcame the devil by the blood of the lamb, for they loved not their lives even unto death"—what does that say? You overcome the devil by the gospel, by believing you are covered by the blood. You overcame by applying and teaching and preaching the blood of Christ, and then by being so sacrificially dedicated to people's lives that you are willing to die rather than run away from a situation. When that happens, when martyrs covered by the blood loving people happens, Satan is defeated.