Christ the Destroyer

In Mark 1:24 the demons said to Christ, "Have you come to destroy us?" and as 1 John 3:8 says, "The reason the Son of God appeared was to destroy the works of the devil." Yet what work of the devil is this referring to? The devil's work to get men to practice sin and to sin against God. Christ has appeared to destroy the practice of sin in a person's life. His power alone can destroy such a practice; as 1 John 3:9 says, "No one born of God makes a practice of sinning, for God's seed abides in him, and he cannot keep on sinning because he has been born of God."