God’s Word for You
Genesis 4:9-10 My brother’s keeper
by Pastor Timothy Smith on Sunday, October 4, 2026
9 Then the LORD said to Cain, “Where is Abel your brother?” He said, “I don’t know. Am I my brother’s keeper?” 10 And the LORD said, “What have you done? The voice of your brother’s blood is crying out to me from the ground.
Cain has sinned against the Fifth Commandment. Luther paints an excellent and memorable picture when he explains the Fifth Commandment by saying we have been “at home, in our house” as we learned the first four commandments, about the spiritual and the civil government, meaning our obedience to God and our obedience to our parents and the government. Now, Luther says, “in this commandment we leave our own house and go out among our neighbors to learn how we should conduct ourselves individually toward our fellow men” (Large Catechism).
But then we also must see that the Fifth Commandment does not apply to God nor to the government when the government is doing its duty to protect its population; their right to take human life is not set aside or abrogated by this command. For, as we learn in Romans 13, a government official, or a soldier, or a police officer, may carry out capital punishment, take life in a war, or take life in order to protect the lives of others. “The government is God’s servant to do you good. But if you do wrong, be afraid, for he does not bear the sword for nothing. He is God’s servant, an agent of wrath to bring punishment on the wrongdoer” (Romans 13:4).
This is not at all what Cain had done, but it is good to remind ourselves of the commandment. Cain murdered out of jealousy. He plotted to take his brother’s life. Then he tried to conceal what he had done, and that act proclaimed his guilt, since when a life is taken justly, it is not covered up or hidden away. If the state executes a murderer, for example, this is announced so that the people will know that their government has protected them. But Abel’s body was nowhere to be found… except that God knows all. In his omniscience, he tells Cain that he hears Abel’s blood crying out to him from the ground. And the Psalm says, “He who avenges blood remembers; he does not ignore the cry of the afflicted” (Psalm 9:12).
The Lord offers him the chance to repent with his gracious question, “Where is Abel your brother?” This showed God’s grace first, because the Holy Spirit records his name as “the LORD,” which is always a reminder of God’s grace and the promises he keeps. Second, the Lord was asking Cain to answer honestly, not to lie, but to explain exactly where his brother’s dead body was hidden away, off in one of Cain’s fields somewhere. And we might speculate, were there vultures in the sky above, circling, circling, circling, to draw a ring in the sky and draw the Lord’s attention to the only true answer to his question?
Cain answers with insolence. He was denying any responsibility for his younger brother. Is this not the true meaning of the Fifth Commandment, not only with the general law against murder, but that we should help and defend our neighbor from all harm and danger. If we would help a friend to fend off a group of wild dogs (as one nameless man or angel helped me in an empty field on a wild and rainy night thirty years ago), then shouldn’t our conscience drive us to help and defend someone when they are even in danger of harm from us, from ourselves? For the commandment shows us that one who murders is not the only one guilty of this sin, but “It also applies to anyone who can do his neighbor good, prevent or resist evil, defend, and save his neighbor so that no bodily harm or hurt happens to him—yet does not do this” (Large Catechism I:189).
Abel’s blood, the Lord says, “is crying out to me from the ground.” Of course, this is partly an anthropomorphism, for blood does not speak. But then, God does not say that the blood speaks. No! It “is crying out,” and since the verb tso’aqim (צֹעֲקִים) is an active participle, it means that the blood of Abel “Cries and cries and cries to me from the ground!” In Revelation, John saw and heard this: “I saw under the altar the souls of those who had been slain because of the word of God and the testimony they had maintained. They called out in a loud voice, ‘How long, Sovereign Lord, holy and true, until you judge the inhabitants of the earth and avenge our blood?’” (Revelation 6:9-10). Surely Abel’s voice among those souls has been singing and crying out the longest, but he has been joined by many more, and sadly there is room for more such martyrs before the world will come to an end.
This text is filled with the Law and with condemnation for Cain and all other murderers. But it is also overflowing with sudden and unexpected Gospel for all martyrs and everyone who suffers on account of the Word of God. What do we see happening here? Is God silent? Not at all! He knows about the hatred. He knows about the murder. He knows, even though no one else does, where the body is. And he knows the one who is guilty. Nothing escapes his notice. Everything is laid bare, and although he hears many lies, he sees all of the truth. This is why Luther says, “This text is full of comfort against the murderers and enemies of the church. It teaches us that our afflictions, blood, and death fill heaven with their cries.”
Does someone object to your faith?
Cain killed Abel on account of his faith.
Do you feel persecuted, put down, or belittled?
God knows all of this, just as he knows everything that happened to your brother, Abel.
Do you feel a twinge of guilt because the things you do, even the godly things you do, have the stain of sin upon them?
Christ died for your sins, and he makes the things you attempt to do perfectly righteous in God’s sight on account of his own blood.
You are a dear child of God, as was Abel your brother. You are as precious to God as was Abel your brother. You are as fully and completely known and understood by God as was Abel your brother.
“Blessed are those who are persecuted because of righteousness, for theirs is the kingdom of heaven.”
“Blessed are the pure in heart, for they will see God.”
In Christ,
Pastor Timothy Smith
Pastor Smith serves St. Paul’s Lutheran Church in New Ulm, Minnesota. To receive God’s Word for You via e-mail, please visit the St. Paul’s Lutheran Church website.