In Genesis chapter four we find the account of Cain and Abel, Adam and Eve’s first two children. In short, Cain assaulted his brother Abel and killed him. Why did not God execute Cain for murdering his brother in cold blood?
The Bible does not give us the reasons. So we have to play detective and figure it out. We cannot know for certainty the whys and wherefores. However we can come up with a theory.
The theory as to why God did not execute Cain for murdering his brother
This was the first murder of a human but certainly not the last.At that time, there was no law against murder. The law and punishment, an eye for an eye and a life for a life, was only given some 2500 years later. Could it be that legally, since no law had been given, capital punishment could not be administered?
It is good to note that God did punish Cain for murdering his brother Abel. Cain was banished from the area where he lived and had to live the life of a fugitive and wanderer. Also God cursed the ground that he would cultivate so that caring for his physical needs would become much harder than for the rest of humanity.
Paul (Hebrews 11:4), John (1 John 3:12), And Jude (Jude 11) all
1 John 3:11-12 (AMP) 11 For this is the message (the announcement) which you have heard from the first, that we should love one another, 12 [And] not be like Cain who [took his nature and got his motivation] from the evil one and slew his brother. And why did he slay him? Because his deeds (activities, works) were wicked and malicious and his brother’s were righteous (virtuous).
Notice that John implies that Cain got his motivation from the “evil one” which would be Satan the Devil. Therefore we can also assume that Cain will merit eternal destruction just like his father, Satan the Devil.
That is the best theory I can up with. If you have a different view then please share. No matter, Cain is not a good example in anything. He followed the ways of the “evil one”, committed a cold-blooded murder and his eternal fate will not be good. No wonder, John tells us not to follow in the path of Cain.