Cain the Murderer
The original Korean text: https://blog.naver.com/stevision/50113166683
This article is written to the effect that you should not misunderstand the incident that God forgave Cain the first murderer so as to say that we also should forgive the murderers.
God was very pleased when he created humans. He blessed them, "Be fruitful and multiply. (Gen 1:28)" This is the blessing that stands in the opposite of murder. Murder is an extremely profane, presumptuous, and evil act that tramples and ignores God's blessing of life and prosperity.
Cain is the one who trampled on this blessing of God. However, God didn't take Cain's life immediately. Cain was cursed in the world as a punishment for murder. That's all. God put a mark on Cain so that no one might kill him.
God did so because there was not yet the law of God that a murderer must be killed. A murder happened in the creation of God, but at that time, God who blessed humans to be fruitful and multiply wanted recovery of the paradise rather than execution of humans.
However, since Cain, humans have only gotten worse. And the wickedness of man was great in the earth (Gen 6:5) (and even murder has become a routine (Gen 4:23)) , so God was very sorry that he had made man on earth (Gen 6:6). God swept away all human beings except Noah and his family from the earth. As Noah came out of the ark, God gave him a strict law: Those who shed the blood of others must shed their own blood (Murderers must be killed) (Gen 9:6). Because to murder a man is to challenge God's authority. And because in particular human beings are noble for they are created in the image of God. Later, God commanded through Moses again: Anyone who has committed a deliberate murder shall be executed.
Therefore, since God, who at first forgave Cain, but later saw the sins of men increasing day by day and commanded, "He who murders must be put to death," it is not right to argue that we must not execute murderers because God didn't kill the murderer Cain.
After Cain, humans did not keep themselves away from sin and repent but became outlaws who trampled on God's blessing of life and prosperity. Thus, God eradicated Cain and his offsprings completely from the earth. We see the genealogy of Jesus in Lk 3. >..., Shem, the son of Noah, the son of Lamech, the son of Methuselah, the son of Enoch, the son of Jared, the son of Mahalaleel, the son of Cainan, the son of Enos, the son of Seth, the son of Adam. (Lk 3:36-17)< Here, Seth is the son God gave to Adam in place of Abel when he died. However, at the time of Noah, all human beings except Noah's family were killed, therefore so were all descendants of Cain, a son of Adam, which we can see from the above line of genealogy. Cain's offsprings, forgetting the sin of their father Cain, lived in sins, so God rooted out Cain's house.
Jesus showed us how great the aftermath of Cain's sin is when he said, "..., that upon you may come all the righteous blood shed on earth, from the blood of innocent Abel to the blood of Zechariah the son of Barachiah, whom you murdered between the sanctuary and the altar. (Mt 23:35)"
Another thing we need to point out is whether God really forgave the murderer David. On the surface, it seems that he was forgiven, but he had to pay such a severe price for murder for he lost four sons on account of his sin. God didn't kill David because there was none to execute him for he was the king, and because God needed David's political status for his plan for Israel. There was no alternative to David for God to establish his kingdom in Israel. David was so severely punished for murder that he groaned, "Would that I died instead of my son!" Therefore, you can't say we have to forgive murderers because David was forgiven sins by being severely punished. The prophet Nathan said to David, "God has forgiven you," which just means David's relationship with God has been restored. (David lost his four sons after that forgiveness. Forgiveness (recovery of relationship) is one thing, and punishment of the sin is another. Bloodshed can be forgiven only by the blood of the murderer.)
Christians should not claim 'the abolition of the death penalty' under the pretext of God's love. Only can he who wants to be cursed instead of the murderer by God make such a reckless claim.