“1 John 3:8: “The Son of God appeared to destroy the works of the devil.”
Revelation 12:10 says, “I heard a loud voice in heaven saying, ‘Now the salvation and the power and the kingdom of our God and the authority of his Christ have come, for the accuser of our brothers has been thrown down, who accuses them day and night before our God.’” Satan’s defeat is sure. But his accusations haven’t ceased.
It is the same with us as it was with Job. Satan says to God about us, They don’t really love you; they love your benefits. “Stretch out your hand and touch all that [they have], and [they] will curse you to your face” (Job 1:11). Their faith isn’t real. Satan accuses us before God, as he did Job. But it is a glorious thing that followers of Jesus have an advocate who “always lives to make intercession for them” (Hebrews 7:25).
John Piper, Satan’s Ten Strategies Against You