Looking at Mark 9:39-43,45,47-48, the new elders or disciples seem to resent that a stranger might use Jesus’ name to expel demons. Our Lord says, “Do not try to stop him. No man performs a miracle using my name can speak ill of me. Anyone who is not against us is with us” (verses 39-40). The power of God works where it wills. Jesus then makes a quick warning against false prophets, stipulating that any who would lead simple believers astray would best be cast into the sea– literally, better off dead. Jesus is not creating a death penalty for heresy; rather, he is remarking that rendering false teaching puts one under severe judgment from God.
Noting that sin often invalidates the life of virtue and clouds our witness, Jesus utilizes Hebraic hyperbole (exaggeration) in saying if your hand causes you to sin– or your foot– or your eye– cut it off or pluck it out. Short of actually maiming ourselves, our Lord is telling us to avoid sin at all costs. If we are to be nation of prophets, we must repent of sin, believe in the Gospel, and proclaim it to others.
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