For he is a minister of God for you unto good. But if you do what is evil, be afraid. For it is not without reason that he carries a sword. For he is a minister of God; an avenger to execute wrath upon whomever does evil
Other versions
King James Version
For he is the minister of God to thee for good. But if thou do that which is evil, be afraid; for he beareth not the sword in vain: for he is the minister of God, a revenger to execute wrath upon him that doeth evil.English Standard Version
for he is God's servant for your good. But if you do wrong, be afraid, for he does not bear the sword in vain. For he is the servant of God, an avenger who carries out God's wrath on the wrongdoer.New International Version
For he is God's servant to do you good. But if you do wrong, be afraid, for he does not bear the sword for nothing. He is God's servant, an agent of wrath to bring punishment on the wrongdoer.