Why was Cain a "tiller of the ground"?
Following God's very last act of creation – that is, the creation of Eve on the first Friday evening – He blessed both Adam and Eve, then gave them their mandate: "Be fruitful and multiply, fill the earth and subdue it; have dominion over the fish of the sea, over the birds of the air, and over every living thing that moves on the earth. I have given you every herb that yields seed ... every tree whose fruit yields seed; to you it shall be for food… Also to every beast, etc... I have given every green herb for food (Genesis 1:28-30).
That night newly created man and the animals ate their first vegetarian meal; it had God's blessing and they were satisfied. Nobody ate anyone else! Genesis 3:8 tells us that in the Garden of Eden Adam and his wife walked with God in the coo1 of the day while, according to The Book of Jubilees, this relationship went on for seven years. Then came the business at the tree of the knowledge of good and evil (Genesis 3:1-13).
God gave the couple the opportunity to confess and ask for forgiveness, but pride stood in the way; they were judged, then evicted from the Garden. An important part of that judgment was directed to Adam and consisted of God's curse, not on Adam but on the ground (Genesis 3:17). God was fully aware that if He had cursed Adam, then in the eyes of later generations it would reflect upon Himself as a poor father to Adam. The principle is given in Genesis 9:20-27 where Noah cursed Ham's son, Canaan, rather than the real culprit, Ham.
It was many years after the eviction from the Garden that Eve had her first child, Cain, and seven years later she had her second son, Able. We are told that Cain was a tiller of the ground while Abel was a keeper of the flock (Genesis 4:2). The "flock" consisted of either sheep or goats while at that time these animals were not used for food but to provide clothing and the atonement sacrifice (Genesis 3:21, 7:2-3, 8:20-22, Leviticus chapter 16 and 17). Both the clothing and the sacrifice were imposed as a result of sin. God entrusted to Abel, the second son rather than to Cain, the important duty of providing for this sacrifice; Cain was left to deal with the cursed ground. Their father, Adam, had received the teachings from God Himself and either knew or was instructed which tasks to allot to each of his first two sons. In any case, God certainly knew Cain's character, and it also become s evident to us as we read Genesis chapter four.