Wickedness in the world
1 When man began to multiply on the face of the land and daughters were born to them,
2 the sons of God saw that the daughters of man were attractive. And they took as their wives any they chose.
"Sons of God" is another term for angels. Many interpret this verse as angels taking human women as their wives - contrary to God's wishes. Thus, God pronounces his judgment of the global flood.
3 Then the LORD said, "My Spirit shall not abide in man forever, for he is flesh: his days shall be 120 years."
Many people say this verse means that God reduced human lifespan to a maximum of 120 years here. But Noah lived on to 950-years-old (Genesis 9:29). A better interpretation is that at this point, God gave people a grace period of 120 years to repent of their sins and and return to him. Tragically, they did not. In the end, God only saved Noah's family of eight people. If that is true then Noah was 480 years old when God gave this warning, which was before he had his sons.
4 The Nephilim were on the earth in those days, and also afterward, when the sons of God came in to the daughters of man and they bore children to them. These were the mighty men who were of old, the men of renown.
Nephilim could mean "fallen ones". Some people interpret that the Nephilim were the offspring of "the sons of God" who "came in to the daughters of man", and that the ""the sons of God" were fallen angels. They support this interpretation with Jude 1:6 which says "And the angels who did not stay within their own position of authority, but left their proper dwelling, he has kept in eternal chains under gloomy darkness until the judgment of the great day-". Although this interpretation is plausible, it is not beyond doubt, and not without its problems. Other views interpret the Nephilim as descendants of Seth in the what is called the Sethite View. The truth is, the Bible gives very few details of what these verses mean and what is provided is ambiguous. It is unwise to speculate and go beyond the Word.
5 The LORD saw that the wickedness of man was great in the earth, and that every intention of the thoughts of his heart was only evil continually.
6 And the LORD was sorry that he had made man on the earth, and it grieved him to his heart.
7 So the LORD said, "I will blot out man whom I have created from the face of the land, man and animals and creeping things and birds of the heavens, for I am sorry that I have made them."
Many people seem confused that God can be omniscient and still have apparent regret as stated in vv.6-7. This is just an example of the Bible speaking anthropomorphically - using language in human terms that we can understand. God knows the end from the beginning, and nothing takes him by surprise. See more about anthropomorphism at Got Questions Ministries.
8 But Noah found grace in the eyes of the LORD.
God doesn't make mistakes. So, he isn't "sorry" in the sense that he wished he had never created Man. But rather that he is somehow grieved at taking the necessary stern action against Man. God is grieved by our sin and he does not shirk in taking the necessary action against it, but he also shows grace. Romans 5:20 says that "where sin increased, grace abounded all the more". And so we should notice here that "Noah found grace (sometimes translated as favour; H2580 chen; pronounced khane) in the eyes of the LORD."
Noah and the flood
9 These are the generations of Noah. Noah was a righteous man, blameless in his generation. Noah walked with God.
"Noah was a righteous man, blameless in his generation. Noah walked with God." It's hard for us to comprehend these words. It's hard even to imagine someone like Noah. There were no men like him in conventional history. Noah wasn't sinless since no one can be except Christ, but he was a unique man.
10 And Noah had three sons, Shem, Ham, and Japheth.
11 Now the earth was corrupt in God's sight, and the earth was filled with violence.
12 And God saw the earth, and behold, it was corrupt, for all flesh had corrupted their way on the earth.
Just as we can't imagine how good Noah was, we probably can't imagine how evil humankind was in this period. The word "corrupt appears" three times in vv.11,12. Hebrew for "corrupt" is H7843 shachath. Phonetic Spelling: (shaw-khath'). Definition: perhaps to go to ruin. The Earth was worse than any dystopian fiction - definitely not a place that we would like to live in. The horrific thing is that Jesus said that Earth will become like "the days of Noah" again before he returns (Matthew 24:37, Luke 17:26). Do you see signs of "the days of Noah" in today's world?
13 And God said to Noah, "I have determined to make an end of all flesh, for the earth is filled with violence through them. Behold, I will destroy them with the earth.
14 Make yourself an ark of gopher wood. Make rooms in the ark, and cover it inside and out with pitch.
15 This is how you are to make it: the length of the ark 300 cubits, its breadth 50 cubits, and its height 30 cubits.
16 Make a roof for the ark, and finish it to a cubit above, and set the door of the ark in its side. Make it with lower, second, and third decks.
17 For behold, I will bring a flood of waters upon the earth to destroy all flesh in which is the breath of life under heaven. Everything that is on the earth shall die.
18 But I will establish my covenant with you, and you shall come into the ark, you, your sons, your wife, and your sons' wives with you.
This is the first time the word covenant appears in the Bible.
19 And of every living thing of all flesh, you shall bring two of every sort into the ark to keep them alive with you. They shall be male and female.
20 Of the birds according to their kinds, and of the animals according to their kinds, of every creeping thing of the ground, according to its kind, two of every sort shall come in to you to keep them alive.
21 Also take with you every sort of food that is eaten, and store it up. It shall serve as food for you and for them."
22 Noah did this; he did all that God commanded him.