Genesis 4:1

And Adam knew Eve his wife; and she conceived, and bare Cain, and said, I have gotten a man from the LORD.

Genesis 4 opens the record of Adam's family after the fall, and with the birth of Cain it begins the history of departure from God's plain commands that filled the world with transgression and sin until God destroyed the world. Cain is introduced as the eldest and firstborn son of Adam and Eve, with Abel as his brother, and Cain became a tiller of the ground in continuation of the soil-tilling appointed when Adam and Eve were sent from Eden, while Abel became a keeper of sheep. Adam and Eve welcomed Cain as their firstborn hoping he would be the promised Deliverer, expecting the promise made in Eden to be fulfilled quickly, but the Saviour did not come in their lifetime. Cain was born into a fallen, divided family under contending influences after Adam and Eve lost their innocence and became transgressors through Satan's successful deception, so that the evil begun in Paradise extended through them and their questionable principles influenced those around them, though with sorrow they told their children the sad story of the fall.

The two sons differed in character, for Abel feared God and was faithful, loyal, obedient and steadfast in keeping God's commandments and directions, while Cain was disloyal, rebellious and disobedient, complained about the curse on Adam and the ground, and refused to obey God. Both had been taught that salvation required humble obedience and faith in the promised Redeemer, and that offering a firstborn lamb with its blood was to express reverence and dependence on God and to keep their sin and the coming Redeemer who would be the great sacrifice for humanity in mind. But Cain resented confessing dependence on Christ through a slain lamb and insisted on carrying out his own ideas, methods and plans in his offering, thinking as the eldest that they should have supremacy and expecting Abel to follow his example.

Between the brothers there could be no harmony, because Abel would not be converted to Cain's way, protested Cain's disloyal principles, and could not concede without disobeying God's special commands, so contention must come. Cain became angry when Abel's offering was accepted and Abel was preferred by the Lord and because Abel would not concede or follow him, and in hatred, persecution and burning anger he killed his brother Abel. In this history the two principles of right and wrong and the two orders or classes in humanity are represented and developed, and from Abel's persecution and death there have continued to the present two classes manifesting the same characteristics. That division stands between those rooted in truth who defend the law of Jehovah and are tested and blessed by God for loyalty and obedience, and those who support falsehood in opposition to truth on the side of the prince of darkness, make void God's law, and, yielding to Satan's will, oppress God's servants just as Cain oppressed Abel, so that keepers of the law are not in favor with the world or with professed Christians, and that history will be repeated.