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Genesis 9:6 deals with the sin of homicide (which, in a sense, is always fratricide, v. 5) and demands a punishment that matches the crime. The justification for capital punishment established here is the nobility of human life, which is in the image of God. Thus murder shows contempt for God as well as for one’s fellow man.
Romans 13:4 shows that the coming of Christ does not abolish capital punishment, but the responsibility is given to government, not individuals. While various methods of death were used, the sword, mentioned in Romans 13:4, stood for the power of life or death. Obviously, as suggested by the principles of justice as seen in the Old Testament, capital punishment should only be carried out after clear evidence and by a just court. For more information on this, you might check out www.probe.org. This is an excellent biblical web site, which deals with a lot of social issues.
The following is taken from an article in the book, The Bible Has the Answer, by Henry Morris and Martin Clark, Creation Life Publishers. I’m sure it will help.
3. Question: “Should capital punishment be abolished?”
Answer: Some duties are thrust upon society, not because they are pleasant, but because they are necessary. Capital punishment is such a duty. It is difficult to imagine anyone enjoying capital punishment; yet that does not mean that it is any less necessary or right. The Christian’s final authority in all matters of faith and practice is not public opinion, but the Bible, God’s Holy Word.
Moses governed Israel with a set of God-given laws, the most familiar of which are the Ten Commandments. Certain laws, such as dietary, civil and ceremonial prescriptions were meant for the Hebrew nation during a particular part of its history. Among these civil laws, the death penalty was required for a number of offenses, including—in addition to murder—adultery (Leviticus 20:10), rape (Deuteronomy 22:25-26), kidnapping (Exodus 21:16), cursing one’s parents (Exodus 21:17), witchcraft (Exodus 22:18), teaching false doctrines (Deuteronomy 13:1-10), Sabbath violations (Exodus 35:2), and several others.
The Bible, however, shows that capital punishment for murder is of a different order than that prescribed under the civil law that governed Old Testament Israel. Following the worldwide Flood, God gave a covenant to Noah, graciously promising never again to send His judgment as a mammoth flood. This same covenant reconstituted human government and established safeguards against the prevailing human violence which precipitated God’s judgment. Central to these safeguards was the death penalty: “Whoever sheds man’s blood, by man his blood shall be shed, for in the image of God He made man” (Genesis 9:6).
Prior to the Flood, men who lived by depraved consciences made themselves odious before the thrice-holy God. “Now the earth was corrupt in the sight of God, and the earth was filled with violence. And God looked on the earth, and behold, it was corrupt; for all flesh had corrupted their way upon the earth. Then God said to Noah, ‘The end of all flesh has come before Me; for the earth is filled with violence because of them; and behold, I am about to destroy them with the earth’” (Genesis 6:11-13). No mere coincidence, then, prompted God to institute the death penalty as a restraint on violence.
Murder was differentiated in Scripture from different degrees of manslaughter, and to murder was relegated the most severe penalty. God’s commandment required the death penalty because “in the image of God He made man” (Genesis 9:6). A murderer not only took the life of his victim, he also assaulted the divine majesty. Taking animal or vegetable life is in no way comparable to taking human life, for though all creation is His handiwork, only man was created in God’s image (Genesis 1:26-27). Nothing else in God’s creation was vitalized by God’s own breath (Genesis 2:7). No matter how sinful man has deformed God’s image, he still bears some likeness of his Creator (James 3:9; 1 Corinthians 11:7).
The death penalty was imposed as a measure of protection for organized society, but purely social considerations fail to give sufficient warrant for the severe punishment. Therefore, God showed the preciousness of human life to be its reflection of His image, and violence against human life constituted rebellion of inestimable magnitude.
The argument that capital punishment only adds a second murder to the first reveals an unfortunate lack of discernment between the violent acts of depraved man and the holy justice of the righteous God. Human government is commissioned to be “a minister of God to you for good. But if you do what is evil, be afraid; for it does not bear the sword for nothing; for it is a minister of God, an avenger who brings wrath upon the one who practices evil” (Romans 13:4).
The fact that ignorance and injustice exist in a judicial system is no excuse for abandoning God’s commandment. The death penalty is drastic, but it need not be rash. Extreme care should be taken to ascertain true guilt or innocence. No one was subjected to more injustice than Jesus Christ in His trial and crucifixion. Indicted on false charges, tried by frenzied bigots, sentenced by a cowardly judge, executed in unspeakable cruelty—what a perfect opportunity to strike out against the whole practice of capital punishment! Yet, God the Son remained quiet. Miscarriages of justice do not warrant abandoning the pursuit of justice. And justice, by God’s standards, includes punitive as well as rehabilitative measures.
God requires that the death penalty be applied to murderers (Genesis 9:5). Changes in cultural mood or in legislation do not alter God’s abiding Word. Though the death penalty may at first seem to be “cruel and unusual punishment,” the Christian should remember that the God of all mercy entrusted it to human government to prevent a far more destructive and corrupting violence.