1The man knew Eve his wife. She conceived, and gave birth to Cain, and said, “I have gotten a man with Yahweh’s help.” 2Again she gave birth, to Cain’s brother Abel. Abel was a keeper of sheep, but Cain was a tiller of the ground. 3As time passed, Cain brought an offering to Yahweh from the fruit of the ground. 4Abel also brought some of the firstborn of his flock and of its fat. Yahweh respected Abel and his offering, 5but he didn’t respect Cain and his offering. Cain was very angry, and the expression on his face fell. 6Yahweh said to Cain, “Why are you angry? Why has the expression of your face fallen? 7If you do well, won’t it be lifted up? If you don’t do well, sin crouches at the door. Its desire is for you, but you are to rule over it.” 8Cain said to Abel, his brother, “Let’s go into the field.” While they were in the field, Cain rose up against Abel, his brother, and killed him.
9Yahweh said to Cain, “Where is Abel, your brother?”
He said, “I don’t know. Am I my brother’s keeper?”
10Yahweh said, “What have you done? The voice of your brother’s blood cries to me from the ground. 11Now you are cursed because of the ground, which has opened its mouth to receive your brother’s blood from your hand. 12From now on, when you till the ground, it won’t yield its strength to you. You will be a fugitive and a wanderer in the earth.”
13Cain said to Yahweh, “My punishment is greater than I can bear. 14Behold, you have driven me out today from the surface of the ground. I will be hidden from your face, and I will be a fugitive and a wanderer in the earth. Whoever finds me will kill me.”
15Yahweh said to him, “Therefore whoever slays Cain, vengeance will be taken on him sevenfold.” Yahweh appointed a sign for Cain, so that anyone finding him would not strike him.
16Cain left Yahweh’s presence, and lived in the land of Nod, east of Eden. 17Cain knew his wife. She conceived, and gave birth to Enoch. He built a city, and named the city after the name of his son, Enoch. 18Irad was born to Enoch. Irad became the father of Mehujael. Mehujael became the father of Methushael. Methushael became the father of Lamech. 19Lamech took two wives: the name of the first one was Adah, and the name of the second one was Zillah. 20Adah gave birth to Jabal, who was the father of those who dwell in tents and have livestock. 21His brother’s name was Jubal, who was the father of all who handle the harp and pipe. 22Zillah also gave birth to Tubal Cain, the forger of every cutting instrument of bronze and iron. Tubal Cain’s sister was Naamah. 23Lamech said to his wives,
“Adah and Zillah, hear my voice.
You wives of Lamech, listen to my speech,
for I have slain a man for wounding me,
a young man for bruising me.
24If Cain will be avenged seven times,
truly Lamech seventy-seven times.”
25Adam knew his wife again. She gave birth to a son, and named him Seth, saying, “for God has given me another child instead of Abel, for Cain killed him.” 26A son was also born to Seth, and he named him Enosh. At that time men began to call on Yahweh’s name.
The meaning of the "sons of God," in this passage has been interpreted three ways: 1) Angels, 2) kings and rulers, and 3) the people of God. The first option draws the interpreter’s attention as follows: Around the second century B.C. the Septuagint, the Greek translation of the Hebrew Bible, translates the “sons of God” in Gen 6:2 as “angels.” 1 Enoch, a Jewish apocryphal literature of the second century B.C., quoted by Jude, also interprets Gen 6:1-4 in terms of the fallen angel’s cohabitation with human women. This view appears to have been held by all of the church fathers prior to St. Augustine. This option is perhaps most appealing in light of the New Testament because the New Testament authors refer to the concept of fallen angels in 2 Pet 2:4 and Jude 6, and its usage in Job 1:6. While 2 Pet 2:4 speaks only of some angels in the days of Noah committing a sin that brought them under God's judgment, the writer Jude provides the nature of the sin that Peter mentions, that it was sexual in nature, as was the sin of Sodom (use of the comparative ὡς in Greek). This option, however, does not answer the question of why God punished men by the Flood if the sons of God were angels unless the text in Genesis speaks of angels who were fallen angels who had already fallen or fell into sin by this act. Furthermore, God bestowed procreative power on animals and humanity (Gen 1:22, 28), not angels. In fact, Jesus denied angels’ procreative ability (Matt 22:30), but this might only speak of angels when they are incorporeal. When angels take on human form, as in Genesis 18 (one, Yahweh Himself), who interacted with Abraham, had their feet washed, and ate a meal with Abraham, it is possible they had other human capabilities.
A second option is that human kings and rulers took any woman of their choice (single or married) for royal harems. In this case, the source of moral decay was the tyrants' polygamy and abuse of power. A difficulty is that the larger context of this text reveals that this text is not about decadent kingship but the moral corruption of humanity as a whole.
The third option views the "sons of God" as the godly men in the lineage of Seth (Gen 4:24-5:32), a view first held by the church father, Augustine. Gen 4:26 deliberately mentions that people during the time of Seth's son Enosh began to call on the name of Yahweh. The "daughters of men" here refer to the ungodly descendants of Cain (Gen 4:17-24). The larger context which leads to this text sets forth the genealogies of godly people (the people of God) and ungodly people (Cainites) and the present text accounts for the fall of the human race in terms of this ungodly union.