Adam and Eve now possess the knowledge of good and evil—a conscience, have been expelled from the garden, and reside in a land that has been cursed because of Adam's sin. When Eve bore her firstborn son, she expressed faith in God's word concerning her seed overcoming Satan (Genesis 4:1—I have acquired a man from the LORD). Soon thereafter, another boy, Abel, was born. Cain worked the ground, but Abel kept sheep (Genesis 4:2). When the time came for them to make an offering to God, Abel brought the firstborn of his flock, but Cain decided to bring the works of his hands. God was not pleased with Cain and, therefore, did not look at his offering. This angered Cain.
Since the failure in the garden, God has not given Adam and Eve new instructions concerning His standard for their lives. One of the rules we find within Scripture is that when a dispensation ends, the steward of that dispensation will not carry on his duties into the new household, for he has failed. In most cases, the new steward was either a member of the previous household who had been spared in its judgment or was born after its end.
It has been roughly thirty years since Adam and Eve were banished from the garden, and now God is going to lay down new standards for the household. Since Adam ate of the tree of the knowledge of good and evil, he was dismissed as the steward. The new household that God is setting up, which includes their children, cannot abide by the rules of the previous one since Adam passed on his corrupt nature to his offspring (Genesis 5:1).
In response to Cain's reaction when his offering was rejected by God, God lays out the rules of the household to him, thereby appointing Cain as the steward of the dispensation of conscience. In Genesis 4:7, God informs Cain that if he does good, it will be accepted, but if he does evil, then the sin nature that he received from his father would use the opportunity to rule over him. Cain's response to his bent nature's desires was to rule over them.
In 1 John 3:12, we are informed that Cain's actions were out from the malignantly evil one—Satan. Rather than obey God, Cain chose the same path Lucifer created through his pride that caused his fall. Cain slew his brother as a sacrifice because Abel's actions were righteous. Abel believed God and offered an acceptable offering, whereas Cain chose to follow the way of self-righteousness (Hebrews 11:4).
As the steward of the dispensation, when Cain slew his brother as a sacrifice, he was not sentenced to death. God caused the ground to no longer produce its strength for Cain and instructed him to be a vagabond on the earth (Genesis 4:11-12). However, Cain still had the duty of supplying the household with the instructions that God gave him concerning the rules of the household. Cain again rejected God’s directives and chose to follow Satan, who used Cain to set up the first world system (Genesis 4:19-24).
Adam’s dispensation lasted approximately one hundred years, whereas Cain’s went on for almost two thousand years. By the end of the dispensation of conscience, all of humanity had rejected good and only sought after calamity all day long (Genesis 6:5).
Through the details recorded concerning this dispensation, we discover that once a man is placed as the steward of a dispensation, he is not replaced, even when his actions result in punishment. We can also determine that the steward of the previous dispensation does not hold that same position in the next household.
For a while, the lines of Seth and Cain stayed separated; however, due to the failure of the household to rule over their sin nature by being obedient to their conscience and doing good, the entire race became corrupt and rejected God. All except one man and his family, whom God saved when He wiped out the humans to stop the malignant evil they were producing because of their choice to reject good.