Cain killed Abel out of envy, for Abel was right with God and Cain was not.
Genesis 4 records that God rejected Cain's offering and accepted Abel's, leaving Cain wroth. Les Feldick identifies envy as the root cause: 'the fact that Abel now is right with God, and he isn't.' Instead of obeying God's warning, Cain rationalized, grew proud, and let his envy turn into the murder of his brother.
Genesis 4:8 — This verse records the actual murder, showing that the killing of Abel followed God's rejection of Cain's offering and the warning about sin.
Genesis 4 tells us that Cain, a tiller of the ground, brought an offering of the fruit of the ground to the Lord, while Abel brought of the firstlings of his flock. The Lord had respect unto Abel and to his offering, but unto Cain and to his offering he had not respect. 'But unto Cain and to his offering he had not respect. And Cain was very wroth, and his countenance fell' (Genesis 4:5). God then warned Cain, 'If thou doest well, shalt thou not be accepted? and if thou doest not well, sin lieth at the door' (Genesis 4:7). Yet, 'Cain talked with Abel his brother: and it came to pass, when they were in the field, that Cain rose up against Abel his brother, and slew him' (Genesis 4:8). The Scripture account does not state the inward motive in so many words, but it places the murder directly after the rejection of Cain's offering and God's warning.
Les Feldick identifies envy as the motive. In Clip 0 he says: 'What's he envious of? Oh, the fact that Abel now is right with God, and he isn't. That's all that's wrong. There's nothing else that has come between these two brothers except this one fact.' God's rejection of his offering made Cain angry (Clip 1), but instead of returning to God in obedience, Cain rationalized—as a farmer, he thought the best of his crops ought to be enough, not realizing (or refusing to admit) that God required a blood sacrifice (Clips 2 and 3). Les also points to pride: Cain was not about to go to his brother and barter for a lamb (Clip 7). God graciously pleaded with him, 'If thou doest well, shalt thou not be accepted?' (Clips 4 and 5), but Cain remained a man 'destitute of faith.' His envy, fueled by anger, rationalization, and pride, culminated in the murder recorded in Genesis 4:8.
Les Feldick contrasts the two sacrifices in Clip 3: Cain's sacrifice was 'something that grew from the ground' and 'cannot shed blood,' while Abel brought 'the best of his flock, a blood sacrifice.' Cain rationalized that his best produce should be enough, reasoning that he did not need to go over the mountain and barter with his brother for a sheep (Clip 2). That was not doing what God said; it was rationalizing. The biblical foundation is Genesis 4:3–5, where Abel's blood offering was respected and Cain's was not.
God did not immediately punish Cain. Instead, He pleaded with him. In Clip 4 Les says, 'God is so gracious. God is so kind. He doesn't just zap Cain. What does he do? He pleads with him.' God asked, 'Why art thou wroth? and why is thy countenance fallen?' and told him, 'If thou doest well, shalt thou not be accepted?' (Genesis 4:6-7). Les points out that God is always anxious for the sinner to make reconciliation by simply doing what God has said (Clip 5).
Yes, according to Les Feldick. God told Cain, 'If thou doest well, shalt thou not be accepted?' and God also offered to provide a sacrifice for him, just as He later provided for Abraham (Clip 7). But pride kept Cain from the remedy—he was not about to go to his brother for a sacrificial animal. Instead of accepting God's gracious provision, he remained in his anger and envy.
Genesis 4:8 is the point where the anger, envy, and pride described by Les Feldick culminate: 'And Cain talked with Abel his brother: and it came to pass, when they were in the field, that Cain rose up against Abel his brother, and slew him.' Les calls Cain a man 'destitute of faith' (Clip 4), and his envy had already been identified in Clip 0 as the fact that Abel was right with God while Cain was not.
Cain's Envious Motive
Les explains that Cain's envy was not over possessions or talents but over the fact that Abel was right with God and he was not.
Cain's Anger at Rejection
Les points out that when God rejected Cain's offering, Cain's first reaction was anger, not repentance.
Cain's Rationalization
Les teaches that Cain rationalized his disobedience, thinking the best of his crops should be accepted rather than bringing the required blood sacrifice.
The Blood Sacrifice Contrast
Les contrasts Cain's bloodless garden offering with Abel's blood sacrifice from the flock, showing why God had respect for Abel's offering.
God's Plea to Cain
Les highlights God's graciousness—instead of striking Cain, God pleaded with him: 'If thou doest well, shalt thou not be accepted?'
Man Destitute of Faith
Les repeats that Cain was destitute of faith and that God was anxious for him to be reconciled by doing what God said.
Cain Departs from the Lord
After the murder, Cain removes himself from contact with God and begins to build a civilization, showing the spiritual separation that followed.
Pride and the Provided Sacrifice
Les explains that pride kept Cain from going to his brother for a lamb, and that God offered to provide a sacrifice for Cain.
Genesis 4:4: And Abel, he also brought of the firstlings of his flock and of the fat thereof. And the LORD had respect unto Abel and to his offering:
Shows that Abel's blood sacrifice was accepted by the Lord.
Genesis 4:5: But unto Cain and to his offering he had not respect. And Cain was very wroth, and his countenance fell.
Shows that Cain's offering was rejected and the immediate anger that followed.
Genesis 4:6-7: And the LORD said unto Cain, Why art thou wroth? and why is thy countenance fallen? If thou doest well, shalt thou not be accepted? and if thou doest not well, sin lieth at the door. And unto thee shall be his desire, and thou shalt rule over him.
God's warning and invitation to Cain to do well and be accepted.
Genesis 4:8: And Cain talked with Abel his brother: and it came to pass, when they were in the field, that Cain rose up against Abel his brother, and slew him.
The biblical record of the murder itself.
Yes, according to Les Feldick. He says Cain was envious because Abel was right with God and he was not (Clip 0). This envy was the root issue—not any other conflict between the brothers.
God asked Cain, 'Why art thou wroth?' and told him, 'If thou doest well, shalt thou not be accepted?' (Genesis 4:6-7). Les points out that God pleaded with Cain instead of striking him down immediately (Clips 4 and 5).
Les Feldick explains that Abel brought a blood sacrifice from his flock, while Cain brought fruit from the ground, which could not shed blood (Clip 3). Cain rationalized his best was enough, but God had specified a different way (Clip 2).
Les Feldick notes in Clip 6 that after the murder, Cain went out from the presence of the Lord and began to build a civilization, showing his separation from God.
Watch the Teaching: Understanding Cain and Abel: Faith, Sin, and Civilization Explained