Ref: Hebrews 2:14-15.
Jesus called Satan a murderer (John 8:44). But his main interest is not killing. It is damning. In fact, he much prefers that his followers have long and happy lives—to mock suffering saints and hide the horrors of hell.
His power to damn human beings lies not in himself, but in the sins that he inspires and the lies that he tells. The only thing that damns anybody is unforgiven sin. […] The one lethal weapon he has is the power to deceive us. His chief lie is that self-exaltation is more to be desired than Christ-exaltation, and sin preferable to righteousness. If that weapon could be taken out of his hand, he would no longer have the power of eternal death.
That is what Christ came to do—take that weapon out of Satan’s hand. To do this, Christ took our sins on himself and suffered for them. When that happened, they could be used no more by the devil to destroy us. Taunt us? Yes. Mock us? Yes. But damn us? No. Christ bore the curse in our place. Try as he will, Satan cannot destroy us. The wrath of God is removed. His mercy is our shield. And Satan cannot succeed against us.
The devil may kill our body, but he can no longer kill our soul. It is safe in Christ. And even our mortal body will be raised someday: “He who raised Christ Jesus from the dead will also give life to your mortal bodies through his Spirit who dwells in you” (Romans 8:11). We are the freest of all people.
—Pages 96, 97
For this reason, the Apostle Paul could say:
“Where, O death, is your victory? Where, O death, is your sting?” The sting of death is sin, and the power of sin is the law. But thanks be to God! He gives us the victory through our Lord Jesus Christ. (1 Cor 15:55-57)