4:2 Abel. “Abel” means “vapor” or “vanity.” By the time Abel was born, Eve was fully aware of the effect of God’s curse on the creation, which was made “subject to vanity” (Romans 8:20).

4:2 tiller of the ground. Both Cain and Abel had honorable occupations, Cain producing food for the family and Abel sheep for clothing and sacrifice. As time would pass and populations would multiply, such specializations could provide the basis for trade and optimum implementation of the Edenic mandate.

4:3 process of time. Literally, “at the end of the days,” undoubtedly a reference to the “seventh day,” which God had hallowed as a day of rest and blessing (Genesis 2:3). On such a day, men would follow God’s example in ceasing from their regular labors in order to have fellowship with God, possibly meeting with Him at the entrance to Eden (Genesis 3:24).

4:3 an offering. Such fellowship, however, required that worshipers approach God with an offering that would make them suitable for His presence. Adam and Eve no doubt had instructed their sons that this required a substitutionary sacrifice of innocent blood (Genesis 3:21). Cain, however, chose to bring another type of offering on this occasion.

4:4 Abel. Abel was a man of faith, the first listed in the chapter of faith (Hebrews 11). Since he brought a “by faith...a more excellent sacrifice” (Hebrews 11:4), it is evident that God had given instruction concerning the sacrifice, which Abel believed and obeyed. The Lord Jesus described him as “righteous” (Matthew 23:35) and even as one of God’s prophets (Luke 11:50,51).

4:5 his countenance fell. Cain’s anger reflects pride in his own works which, because of that very fact, God regarded as “evil” (I John 3:12).

4:6 Why art thou wroth. God’s questions reminded Cain that he knew the type of sacrifice required and had no reason to be surprised when God would not accept another.

4:7 rule over him. Note the similar terminology to that of Genesis 3:16b. Just as Eve’s desire would be toward Adam and he would lead her, so would an unrepentant Cain become so committed to rebellion that “Sin” (personified as a crouching animal) would become Cain’s obedient servant.

4:8 talked with Abel. Abel was a prophet and no doubt urged Cain to repent and believe God’s Word, but this only angered Cain further. The Serpent was quickly striking at the Seed of the woman, corrupting her first son and slaying her second, trying to prevent the fulfillment of the Protevangelic promise.

4:9 I know not. Cain thus added blatant lying to his sins of self-righteous pride and murder. However, in one sense, he was speaking the truth. He knew where Abel’s blood was spilled but not where Abel himself was. Abel was now the first human inhabitant of Sheol (or Hades), that place in the heart of the earth where departed spirits would reside while awaiting the coming of the Savior (Luke 16:22-26; Ephesians 4:8-10; I Peter 3:18-20).

4:10 thy brother’s blood. This first mention of “blood” in Scripture prefigures the innocent blood of Christ, which “speaketh better things than that of Abel” (Hebrews 12:24). The voice of Abel’s blood cried for vengeance (compare Revelation 5:9, 10), but the blood of Christ speaks of cleansing and forgiveness (I John 1:7; Ephesians 1:7).

4:11 cursed from the earth. The earth had been cursed because of Adam’s sin; now the earth itself had been defiled by Cain’s sin. God’s curse was on the earth; Cain’s curse was from the earth. His boastful pride in the fruits he had been able to grow from the cursed earth had been the occasion of his sin, but now he would no longer be able to till the ground even for his own food. Those who trust in their own good works eventually find it impossible to produce them any more.

4:12 vagabond. As yet there was no law given to order man’s behavior. Therefore Cain’s crime could not be punished by governmental means, but only by its natural consequences.

4:13 punishment. The word “punishment” is usually translated “iniquity,” and its use by Cain indicates that, for the first time, Cain acknowledged his sin and guilt to the Lord. This may partially explain the degree of mercy shown by God in sparing his life after Abel’s murder.

4:14 every one. Adam had daughters as well as sons (Genesis 5:4), and brother/sister marriages were necessary at least in the first generation, before the accumulation of genetic mutations could make such close marriages genetically dangerous. Since the antediluvians lived for hundreds of years and since they could propagate children for hundreds of years (note Genesis 5:15,32), the population multiplied rapidly. This concern of Cain’s, therefore, was quite realistic. Since Cain could not produce his own food, he would have to purchase it from others, but other people would naturally tend to fear him and try to avoid him or even to do away with him.

4:15 mark. The “mark” is not described. The Hebrew word oth is better rendered “sign.” Whether this sign was a physical marking on Cain’s body or a miraculous display of some sort, it was widely known for many generations (see Genesis 4:24) and did serve to inhibit any who might be inclined to slay Cain otherwise.