(1-2) God creates and blesses mankind, the Adam.
(3-5) Adam’s lifespan is 930 years.
(6-8) Seth’s lifespan is 912 years.
(9-11) Enos’ lifespan is 905 years.
(12-14) Cainan’s lifespan is 910 years.
(15-17) Mahalaleel’s lifespan is 895 years.
(18-20) Jared’s lifespan is 962 years.
(21-24) Enoch’s lifespan is 365 years. Enoch walks with God, and God takes him.
(25-27) Methuselah’s lifespan is 969 years. Methuselah is known as the oldest man.
(28-31) Lamech’s lifespan is 777 years. The Greek Septuagint states 753 years.
(5:32) When Noah was 500 years old, he begets three sons: Shem, Ham, and Japheth.
(6:1-6:4) Mankind multiplies with many daughters born to them. The sons of God, fallen angels, take these daughters as wives. YHWH limits man’s lifespan to 120 years. The result of the union between the sons of God and the daughters of men are powerful men. These might be Neanderthral men, since the bloodline of the Neanderthal has come through the lineage of Japheth.
After the beginning of the world, the flood occurred 2262 years later. The only one to survive the flood was Noah. According to the Masorectic Text, Lamech would have died after the flood. However, the Masorectic Text does not include Lamech as one of the eight ark survivors. Thus, the Septuagint Text is more accurate.
(5-8) Because of the wickedness of mankind, YHWH repents and grieves that he has made them. YHWH decides to destroy mankind and the animal life. However, Noah has found grace in the eyes of YHWH.