Cain and Abel
1 Now Adam knew Eve his wife, and she conceived and bore Cain, saying, "I have gotten a man with the help of the LORD."
2 And again, she bore his brother Abel. Now Abel was a keeper of sheep, and Cain a worker of the ground.
3 In the course of time Cain brought to the LORD an offering of the fruit of the ground,
4 and Abel also brought of the firstborn of his flock and of their fat portions. And the LORD had regard for Abel and his offering,
To offer "fat portions" means Abel must have killed an animal, and God found his sacrifice acceptable, but God rejected Cain's plant-only offering. God's reason for rejecting Cain's offering is given in v.7.
5 but for Cain and his offering he had no regard. So Cain was very angry, and his face fell.
6 The LORD said to Cain, "Why are you angry, and why has your face fallen?
7 If you do well, will you not be accepted? And if you do not do well, sin is crouching at the door. Its desire is for you, but you must rule over it."
Cain did not "do well". God saw Cain's heart and his sin. We aren't exactly told what that sin was, and that's intentional, because the principle is true for all sins. We all fail to "do well" and sin. It is probable that Cain knew what God required as an offering i.e. sacrifice involves the shedding of blood, but chose his own offering rather than the one God had commanded. Do we offer what God desires? Do we worship God in the way he commands us to? Do we believe what God commands to believe and disbelieve what God commands us to disbelieve? Or do we devise our own offerings and worship, believe whatever we want, and pretend that God is pleased with us? If we do then we are committing the same sin as Cain.
8 Cain spoke to Abel his brother. And when they were in the field, Cain rose up against his brother Abel and killed him.
9 Then the LORD said to Cain, "Where is Abel your brother?" He said, "I do not know; am I my brother's keeper?"
10 And the LORD said, "What have you done? The voice of your brother's blood is crying to me from the ground.
11 And now you are cursed from the ground, which has opened its mouth to receive your brother's blood from your hand.
12 When you work the ground, it shall no longer yield to you its strength. You shall be a fugitive and a wanderer on the earth."
13 Cain said to the LORD, "My punishment is greater than I can bear.
14 Behold, you have driven me today away from the ground, and from your face I shall be hidden. I shall be a fugitive and a wanderer on the earth, and whoever finds me will kill me."
Detractors say if there were other people to kill Cain then God must've have created other humans besides Adam and Eve. God doesn't make glaring mistakes in the Bible for such detractors to pick up on. They are just being sloppy in reading the Bible. Genesis 5:4 tells us that Adam had other sons and daughters. In fact, he must've had many, since he lived until he was 930. We don't know how old Cain and Abel were when the first fraticide occurred. There may well have been several generations of Adam's descendants by then. The logical explanation is that Cain was scared that his other siblings and their progeny, who all knew and loved Abel, would seek revenge.
15 Then the LORD said to him, "Not so! If anyone kills Cain, vengeance shall be taken on him sevenfold." And the LORD put a mark on Cain, lest any who found him should attack him.
16 Then Cain went away from the presence of the LORD and settled in the land of Nod, east of Eden.
17 Cain knew his wife, and she conceived and bore Enoch. When he built a city, he called the name of the city after the name of his son, Enoch.
Another common question is "Who was Cain's wife?". The simple answer was probably his sister, neice, or some other relative. And to those who cry "incest" we need to know that God did not ban incest until later in human history - in the time of Moses. In the antediluvian humans, DNA hadn't deteriorated to the stage where marriage between near relatives would cause genetic defects in their offspring. Those who cry "incest" need to understand that no man and woman could be closer than Adam and Eve who were effectively twins.
18 To Enoch was born Irad, and Irad fathered Mehujael, and Mehujael fathered Methushael, and Methushael fathered Lamech.
19 And Lamech took two wives. The name of the one was Adah, and the name of the other Zillah.
20 Adah bore Jabal; he was the father of those who dwell in tents and have livestock.
21 His brother's name was Jubal; he was the father of all those who play the lyre and pipe.
22 Zillah also bore Tubal-cain; he was the forger of all instruments of bronze and iron. The sister of Tubal-cain was Naamah.
23 Lamech said to his wives: "Adah and Zillah, hear my voice; you wives of Lamech, listen to what I say: I have killed a man for wounding me, a young man for striking me.
24 If Cain's revenge is sevenfold, then Lamech's is seventy-sevenfold."
25 And Adam knew his wife again, and she bore a son and called his name Seth, for she said, "God has appointed for me another offspring instead of Abel, for Cain killed him."
After Abel's death, we don't know how many years went by before Eve had Seth. If it was much later, Adam and Eve may well have had many other children before Seth.
Biblical genealogies are important because they trace the line from Adam to Jesus himself. Seth is mentioned in the geneaology of Jesus in Luke 3:38.
26 To Seth also a son was born, and he called his name Enosh. At that time people began to call upon the name of the LORD.
What does this verse mean? Why did people only "began" to call upon the name of the LORD here? What did they do before this? Some say that God still appeared to his people up until this point.