Genesis 6 opens with a problem that is not abstract. Men multiplied on the ground. Daughters were born. The sons of God saw that the daughters of men were fair, and they took wives from among them, as many as they chose. The text does not pause to explain who the sons of God were. It simply reports the fact and moves on. The Lord then declared that His Spirit would not strive with man forever, because man also was flesh. He set a limit: a hundred and twenty years. That is the first concrete action the Lord takes in the chapter, and it is a limit, not yet a judgment.
The Nephilim were in the earth in those days, and also afterward. The text says they were the mighty men of old, the men of renown. But the chapter does not linger on them. It turns immediately to what the Lord saw: that the wickedness of man was great on the earth, and that every imagination of the thoughts of his heart was only evil continually. That is a comprehensive statement. There is no room for a righteous remnant in that description, except for one man.
The Lord repented that He had made man on the earth, and it grieved Him at His heart. That is the emotional center of the chapter. The Lord did not act out of cold calculation. He was grieved. He said He would destroy man from the face of the ground, along with the beasts, the creeping things, and the birds, because it repented Him that He had made them. But Noah found favor in the eyes of the Lord.
Noah is introduced with a formal genealogical phrase: these are the generations of Noah. He was a righteous man, perfect in his generations. He walked with God. That is the only description the chapter gives. He had three sons: Shem, Ham, and Japheth. The earth was corrupt before God, filled with violence. God saw the earth, and it was corrupt, for all flesh had corrupted their way on the earth.
Then God spoke directly to Noah. He said the end of all flesh had come before Him, because the earth was filled with violence through them. He said He would destroy them with the earth. That is the first time the flood is mentioned, and it is stated as a settled intention. The Lord did not negotiate. He gave Noah a command: make an ark of gopher wood, with rooms, pitched inside and out with pitch.
The dimensions are given precisely: three hundred cubits long, fifty cubits wide, thirty cubits high. A cubit is roughly eighteen inches, so the ark was about four hundred fifty feet long, seventy-five feet wide, forty-five feet high. It had a light opening finished to a cubit upward, a door in the side, and three stories. The Lord said He would bring a flood of waters on the earth to destroy all flesh under heaven that had the breath of life. Everything on earth would die.
But the Lord established a covenant with Noah. Noah, his sons, his wife, and his sons' wives would enter the ark. Of every living thing, two of every sort, male and female, would come to Noah to be kept alive. Birds, cattle, creeping things—two of every sort. Noah was also to gather food for himself and for the animals.
The chapter ends with a single sentence: Thus did Noah; according to all that God commanded him, so did he. There is no dialogue from Noah. No prayer, no protest, no question. The text does not say whether Noah understood the scope of what he was building. It only says he did what he was told. The chapter does not describe the construction, the neighbors, the weather, or the time it took. It leaves the reader with the weight of the command and the obedience.
The chapter does not moralize. It does not explain why the Lord chose Noah or why the rest of humanity deserved destruction. It simply records the corruption, the grief of God, the command, and the obedience. The flood itself is not narrated in this chapter. That comes in chapter 7. Here, the story stops at the point of decision: the ark is commanded, and Noah does it.