10 And the Lord said, “What have you done? The voice of your brother’s blood is crying to me from the ground. 11 And now you are cursed from the ground, which has opened its mouth to receive your brother’s blood from your hand. 12 When you work the ground, it shall no longer yield to you its strength. You shall be a fugitive and a wanderer on the earth.” 13 Cain said to the Lord, “My punishment is greater than I can bear. 14 Behold, you have driven me today away from the ground, and from your face I shall be hidden. I shall be a fugitive and a wanderer on the earth, and whoever finds me will kill me.” 15 Then the Lord said to him, “Not so! If anyone kills Cain, vengeance shall be taken on him sevenfold.” And the Lord put a mark on Cain, lest any who found him should attack him. 16 Then Cain went away from the presence of the Lord and settled in the land of Nod, east of Eden. 
One of the worst things about being a parent is watching your children make the same mistakes you have made despite your best efforts to teach them otherwise. It’s painful for parents to watch their own sins reflected back to them in children’s behavior. Imagine how it must have felt for Adam and Eve, through whom death entered the world by their sin, to know their oldest son murdered his brother. Nothing could compare to the heartache of watching the son they had raised to be the savior of mankind descend into open hatred of God and God’s people. This was part of the common curses of the Covenant of Works – that the mother would endure not only pain of birth, but also the pain of seeing her children’s sins, “in pain you shall bring forth children.”
When the first mother held the first human born into the world she said, “I have gotten the man with the help of the Lord” (4:1). Certain the first child was the Promised Seed (3:15), she named her second child, heḇēl – Nothing. Cain was to become the new prophet-priest-king who would crush the serpent’s head and lead humanity past the cherubim’s flaming swords back into God’s perfect garden-temple. Poor “Nothing” was just along for the ride. Is it any wonder that the son raised to believe he was God’s gift to the world would bring a thank offering that celebrated his own accomplishments while the son raised as “Nothing” brought an offering with an attitude of humble trust into God’s grace?
The kind of offering the brothers brought was not the problem. God looks upon the person, not their works. The person does not become righteous by virtue of their works, but a work becomes righteous because of the person’s faith. Luther wrote:
He rejects Cain, not because his sacrifice was inferior (for if he had brought the shell of a nut in faith as a sacrifice, it would have been pleasing to God), but because his person was evil, without faith, and full of pride and conceit. By contrast, He has regard for Abel’s sacrifice because He is pleased with the person. Accordingly, the text distinctly adds that first He had regard for Abel and then for his sacrifice. For when a person pleases, the things he does also please, while, on the contrary, all things are displeasing if you dislike the person who does them.
Therefore this passage is an outstanding and clear proof that God does not have regard for either the size or the quantity or even for the value of the work, but simply for the faith of the individual. Similarly, by contrast, God does not despise the smallness, the lack of value, or the lowly nature of a work, but only a person’s lack of faith.
St. Author of Hebrews explained, “…without faith it is impossible to please him, for whoever would draw near to God must believe that he exists and that he rewards those who seek him.”
Abel was the victim of the first worship war, the first religious dispute in history. After sin entered the world, all children of Adam and Eve are born with the natural desire to reject God and earn their own self-defined merit. Man’s religion is about outward performance. “If I feel good about myself, I will be happy; if I impress you in the process, I will be even happier.” Cain approached God on the basis of his self-supposed merit as the promised seed. Abel approached God as Nothing. David the murderer, cut off from making any atoning sacrifice for his sin, sang in his great song of repentance, “The sacrifices of God are a broken spirit; a broken and contrite heart, O God, you will not despise.” It wasn’t Cain’s form of worship God rejected; it was Cain’s self-worship.
The bedrock theology, so often unseen in this text, is that our rightness with God does not come by means of outward appearance or any form of worship (grain-based or animal-based). A human being, rather than their works, must be just. They are accepted by God without any works of their own, solely through grace which faith understands and believes. Not even faith as a work makes one right with God; faith (trust) makes one right with God because it understands the grace offered in the person and work of the Lord Jesus Christ – the true Promised Seed of the woman. “The true church walks in this trust in God’s mercy, together with a humble confession of its sins and unworthiness, which hopes that God will grant His pardon through Christ. …the works which follow are evidences… of this faith; they please God, not …on their own account but because of faith or because of the believing person.”
TRIAL AND SENTENCING (9-12)
Following Abel’s murder, Cain presumably buries the body. No body; no evidence. But when the homicide detective is also the eyewitness, the prosecutor and the judge – THE ALL-KNOWING GOD – hiding the body is a waste of effort. “9 Then the Lord said to Cain, “Where is Abel your brother?” He said, “I do not know; am I my brother’s keeper?” Cain’s flippant, indifferent reference to his dead brother revealed a heart hardened in its depravity. Sarcasm became the murderer’s refuge. Paul would write:
28 And since they did not see fit to acknowledge God, God gave them up to a debased mind to do what ought not to be done. 29 They were filled with all manner of unrighteousness, evil, covetousness, malice. They are full of envy, murder, strife, deceit, maliciousness.
Many a trial lawyer would say, “When that law isn’t on your side, pound on the facts. When the facts aren’t on your side, pound on the table.” Cain must have invented that saying because all he can do is pound on the defense table and shout back at God. Cain knows exactly where Able is, AND Cain had been raised as the promised seed. By definition, the promised seed is not only his brother’s keeper but the keeper of the whole human race! Cain is clearly demonstrating he is the seed of his father the devil.
10 And the Lord said, “What have you done? The voice of your brother’s blood is crying to me from the ground.” God makes a simple, two-word accusation (in Hebrew), translated for us as “What have you done!” (lit: What [you done]). It’s even shorter than his accusation of Eve in 3:13 (lit: What this [you done]). Like his interaction with Eve, this is not a question but a declarative statement deserving an exclamation point rather than a question mark. The context makes that clear with the next sentence, “The voice of your brother’s blood is crying to me from the ground.”
The word used here for crying (blood is crying) often describes the cry of the oppressed, like the afflicted in Sodom and Gomorrah (Gen. 18:13), the overworked and exhausted Israelites in Egypt (Exod. 3:7), or the oppressed stranger, widow, or orphan (Exod. 22:21–24). In the Old Testament, blood and life belong to God alone. Murder attacks God’s right to own his image-bearers. Destruction of human life steps outside man’s God-ordained boundaries. It is the ultimate oppression. In the Mosaic law, there was no reprieve for the murderer and no atoning sacrifice for his sin.
Every criminal trial has two phases – a guilt-innocence phase and a sentencing phase. Since God was the eye witness, the homicide detective, prosecutor, judge and jury, the guilt-innocence phase of Cain’s trial gets two brief sentences in Moses’ story. The sentencing phase lasts for five verses. First, God pronounces his judgment, “11 And now you are cursed from the ground, which has opened its mouth to receive your brother’s blood from your hand. 12 When you work the ground, it shall no longer yield to you its strength. You shall be a fugitive and a wanderer on the earth.” 
This is the first time in scripture where a human is cursed by God. Cain joins the devil in this sad distinction. The curse language is the same as in 3:14. It’s a kicked-up-a-notch version of the common curse pronounced on all mankind following Adam’s sin. For Adam, the ground would provide food as long as Adam worked hard for it, fighting the thorns and weeds. But for Cain who shed human blood into it, the ground will no longer produce. The fact that he becomes a “wandering fugitive” is a consequence of the curse, not a part of the curse.
This curse is far less than Cain deserves. What Cain really deserved was death. Five chapters later in Genesis, God institutes capital punishment. He says to Noah, “Whoever sheds the blood of man, by man shall his blood be shed” (Gen. 9:6). If death is God’s appointed punishment for murder and man is later given authority to pronounce this punishment, then God had every right to put Cain to death. Yet he did not because of his great mercy to our race. His desire was to populate the earth with the just and the unjust alike.
However, in some ways, Cain faces a fate worse than death. He loses all sense of belonging to a community. He is now rootless and detached. But he would not merely become a wandering fugitive— the curse went beyond that. “All his relationships with his family were broken. He was a lifelong pariah. The earth itself would be his enemy. Cain, who had once worked the soil, had watered it with his brother’s blood. That blood had cried against him from the soil, so that he was banned from it forever— to wander over it as an enemy of the earth.”
We want to view Cain as the first great villain of history. But he is also a tragic character – the victim of his parents’ sin and of his own sin he had no power to master. Rootlessness is the consequence of his sin. Like Ishmael and Esau, like the faithless Israelites, he becomes a wanderer in the wilderness. But Cain protests the curse and the consequences of his sin. He doesn’t repent; he proclaims his inwardly curved worldly sorrow (2 Cor. 7:10). Cain’s lament is the beginning of worldly sorrow. The apostle John, in Revelation 16:10-11, pictures the city of man’s response to judgment, “People gnawed their tongues in anguish 11 and cursed the God of heaven for their pain and sores. They did not repent of their deeds.” 
Cain cries in verse 13, “My punishment is greater than I can bear. 14 Behold, you have driven me today away from the ground, and from your face I shall be hidden. I shall be a fugitive and a wanderer on the earth, and whoever finds me will kill me.” This suggests there were other people in the world besides Adam, Eve, and Cain. Who are these people and where do they come from?
Textual critics say the Cain story was a later narrative tacked onto the Adam and Eve chronicle. Some students of scripture suggest there were other humans alive but that only Adam and Eve were specially created by God and placed in the garden as representatives of all mankind. Or, we can hold to the idea that Adam, Eve, Cain, Abel, and Seth are the only children of Adam and Eve specifically mentioned and named in this part of Moses’ account. Moses is concerned with communicating the doctrine of the Godly and the unredeemed lines of descendants as represented by Cain, Able, and Seth.
Assuming a family being fruitful and multiplying over centuries, Cain’s wife would be his sister. Those who might kill Cain would be Cain’s brothers and sisters and nieces and nephews. If that is the case, and it is the one I prefer based on the text, then the situation is even more weighted with irony. He who murdered one of his relatives now must watch out for any of his relatives out for vengeance who wish to murder him.
This is further evidence how sin has taken hold on humanity in one generation. Cain would not be the only member of his family with murder and vengeance in his heart. We know that to be the case since God doesn’t dispute Cain’s conclusion that he is subject to murder. Unlike Adam and Eve, God knows true good and evil and the hearts of all humanity are open to him at all times. Even the line of redeemed descendants are simultaneously saints and sinners; and as sinners, they are just as capable of murder as Cain. Through one man, sin entered and worked its way into every atom of every human – be they God-trusting or God-hating.
For the believer it’s amazing how a little awareness of sin’s consequences will shift your relationship with God from entitlement to mercy. But for Cain, there was only his life-long sense of entitlement. Yet, God was still merciful. First, he did not kill Cain. Second, he placed a mark of protection on him so that Cain would not meet a violent death as Able had. Verse 15, “Then the Lord said to him, “Not so! If anyone kills Cain, vengeance shall be taken on him sevenfold.” And the Lord put a mark on Cain, lest any who found him should attack him.”
Like many things the Holy Spirit chooses not to tell us in Genesis, we are not told how God marks Cain for protection. That has not stopped inquisitive people from wasting time speculating about it. Suppositions range from tattoos to hairstyles to guard dogs. Some scholars say the word “mark” is a mistranslation of the word oath. Certainly, God’s promise of seven-fold vengeance is oath language. The point of the verse is that God is merciful even to unrepentant sinners. “For he makes his sun rise on the evil and on the good, and sends rain on the just and on the unjust.” Cain’s life still belonged to God alone. However much sin had marred it, Cain still bore God’s image.
God takes his image in humanity seriously – far more so than any of us do most of the time. If you don’t believe me, go check out social media and see how those who claim to be Christians vilify others over theology, politics and social issues. We love to murder other bearers of the divine image with our words, as long as we convince ourselves it’s for a righteous cause. Usually, our idea of a righteous case is someone holding a different opinion that must be corrected or opposed. Anything I want that you stand in the way of is a righteous cause to me. But for God’s restraining hand, I will do anything I can to get what I want regardless of whether you bear God’s image as God’s special creature. By our sin nature, we are all Cain. Our preferred weapon may be our words, but we desire to destroy what we cannot control.
Moses concludes this story of Cain’s judgment in verse 16, “16 Then Cain went away from the presence of the Lord and settled in the land of Nod, east of Eden.”  The clear assumption made throughout Gen. 4 is that God and Cain are bodily present in their setting, which is somewhere east of the garden of Eden. Leaving God’s presence is Moses’ way of telling us how Cain entered his life of alienation from God. The word “Nod” sounds like the verb to wander (4:14). Cain the wandering fugitive left God’s presence to live in the Land of Wandering. Nod is “eastward of Eden,” a direction that further emphasized Cain’s detachment from both God and the rest of Godly humanity.
The way of Cain is hard. One commentator [Barnhouse] writes, “He started with human reason as opposed to divine revelation; he continued in human willfulness instead of divine will; …he sank to human hatred instead of rising to divine love; he presented human excuses instead of seeking divine grace; he went into wandering instead of seeking to return; he ended in human loneliness instead of in divine fellowship. To be alone without God is the worst thing that earth can hold, to go thus into eternity is, indeed, the second death.” Cain, we are told, “went out from the Lord’s presence and lived in the land of Nod, east of Eden” (v. 16). Do not let it be true of you that you “went out from the Lord’s presence.”
To be far from God’s presence is to be a wandering fugitive in the wilderness – a place of restlessness without peace. But by trusting into the perfect life Jesus lived so that he can provide your perfection without which no one can enter near to God, and by trusting into his sacrificial death as payment for the wages of our sins you can have peace in a new home, a new community, near to your Creator.
13 But now in Christ Jesus you who once were far off have been brought near by the blood of Christ. 14 For he himself is our peace…. 17 And he came and preached peace to you who were far off and peace to those who were near. 18 For through him we both have access in one Spirit to the Father. 19 So then you are no longer strangers and aliens, but you are fellow citizens with the saints and members of the household of God, 20 built on the foundation of the apostles and prophets, Christ Jesus himself being the cornerstone, 21 in whom the whole structure, being joined together, grows into a holy temple in the Lord. 22 In him you also are being built together into a dwelling place for God by the Spirit. 
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:10–16.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 3:16.
 Luther, 258.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Heb 11:6.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ps 51:17.
 Luther, 259.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ro 1:28–29.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:9–10.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:10.
 Hamilton, 231.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:11–12.
 Hamilton, 232.
 Boice, 256.
 Hughes, 106. Kindle Edition.
 Hamilton, 232–233.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Re 16:10–11.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:13–14.
 Hamilton, 233.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:15.
 Kline, Genesis: A New Commentary, 26.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Mt 5:45.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Ge 4:16.
 Hamilton, 235.
 Boice, 260–261.
 The Holy Bible: English Standard Version (Wheaton, IL: Crossway Bibles, 2016), Eph 2:13–22.