36. Heed, then, this passage. It establishes civil authority as God's institution, with power, not only of life and death, but jurisdiction in matters where life is not involved. Magistrates are to punish the disobedience of children, theft, adultery, perjury—all sins which are forbidden in the second table. He who grants jurisdiction over the life of man, at the same time grants judgment over lesser matters.
37. The importance of this text and its claim to attention consists in the fact that it records the establishment of civil authority by God with the sword as insignia of power, for the purpose that license may be curbed and anger and other sins inhibited from growing beyond all bounds. Had God not granted this power to man, what kind of lives, I ask you, would we lead? He foresaw that wickedness would ever flourish, and established this external remedy to prevent the indefinite spread of license. By this safeguard God protects life and property as by a fence and a wall.
38. We find here no less a proof of God's great love toward man than his promise that the flood shall never again rage, and his promise that flesh may be eaten for the sustenance of human life.
V. 6b. For in the image of God made he man.
39. This is the powerful reason why God does not wish men to be killed by private arbitrament. Man is a noble creature, who, unlike other living beings, has been fashioned according to the image of God. While it is true that he has lost this image through sin, as we have seen above, it is capable of being restored through the Word and the Holy Spirit. This image God desires us to revere in each other; he forbids us to shed blood by the exercise of sheer force. But he who refuses to respect the image of God in man, and gives way to anger and provocation, those worst counselors of all, as some one has called them, his life is surrendered to civil authority in forfeit, by God, in that God commands that also his blood shall be shed.