3 So it came about in the course e of time that Cain brought an offering to the Lord of the fruit of the ground . 4 Abel , on his part also brought of the firstlings of his flock and of their fat portions . And the Lord had regard for Abel and for his offering ; 5 but for Cain and for his offering He had no regard . So Cain became very angry and his countenance fell .

6 Then the Lord said to Cain , " Why are you angry ? And why has your countenance fallen ? 7 " If you do well , will not your countenance be lifted up? And if you do not do well , sin is crouching at the door ; and its desire is for you, but you must master it."

8 Cain told Abel his brother . And it came about when they were in the field , that Cain rose up against Abel his brother and killed him.

Matthew Henry's Commentary on Genesis 4:3-8

Commentary on Genesis 4:1-7

(Read Genesis 4:1-7)

When Cain was born, Eve said, I have gotten a man from the Lord. Perhaps she thought that this was the promised seed. If so, she was wofully disappointed. Abel signifies vanity: when she thought she had the promised seed in Cain, whose name signifies possession, she was so taken up with him that another son was as vanity to her. Observe, each son had a calling. It is the will of God for every one to have something to do in this world. Parents ought to bring up their children to work. Give them a Bible and a calling, said good Mr. Dod, and God be with them. We may believe that God commanded Adam, after the fall, to shed the blood of innocent animals, and after their death to burn part or the whole of their bodies by fire. Thus that punishment which sinners deserve, even the death of the body, and the wrath of God, of which fire is a well-known emblem, and also the sufferings of Christ, were prefigured. Observe that the religious worship of God is no new invention. It was from the beginning; it is the good old way, Revelation 3:20. And those well deserve to perish in their sins, that will not go to the door to ask for the benefit of this sin-offering. God's acceptance of Abel's offering did not change the birthright, and make it his; why then should Cain be so angry? Sinful heats and disquiets vanish before a strict and fair inquiry into the cause.

Commentary on Genesis 4:8-15

(Read Genesis 4:8-15)

Malice in the heart ends in murder by the hands. Cain slew Abel, his own brother, his own mother's son, whom he ought to have loved; his younger brother, whom he ought to have protected; a good brother, who had never done him any wrong. What fatal effects were these of our first parents' sin, and how must their hearts have been filled with anguish! Observe the pride, unbelief, and impenitence of Cain. He denies the crime, as if he could conceal it from God. He tries to cover a deliberate murder with a deliberate lie. Murder is a crying sin. Blood calls for blood, the blood of the murdered for the blood of the murderer. Who knows the extent and weight of a Divine curse, how far it reaches, how deep it pierces? Only in Christ are believers saved from it, and inherit the blessing. Cain was cursed from the earth. He found his punishment there where he chose his portion, and set his heart. Every creature is to us what God makes it, a comfort or a cross, a blessing or a curse. The wickedness of the wicked brings a curse upon all they do, and all they have. Cain complains not of his sin, but of his punishment. It shows great hardness of heart to be more concerned about our sufferings than our sins. God has wise and holy ends in prolonging the lives even of very wicked men. It is in vain to inquire what was the mark set upon Cain. It was doubtless known, both as a brand of infamy on Cain, and a token from God that they should not kill him. Abel, being dead, yet speaketh. He tells the heinous guilt of murder, and warns us to stifle the first risings of wrath, and teaches us that persecution must be expected by the righteous. Also, that there is a future state, and an eternal recompence to be enjoyed, through faith in Christ and his atoning sacrifice. And he tells us the excellency of faith in the atoning sacrifice and blood of the Lamb of God. Cain slew his brother, because his own works were evil, and his brother's righteous, 1 John 3:12. In consequence of the enmity put between the Seed of the woman and the seed of the serpent, the war broke out, which has been waged ever since. In this war we are all concerned, none are neuter; our Captain has declared, He that is not with me is against me. Let us decidedly, yet in meekness, support the cause of truth and righteousness against Satan.