When mankind began to multiply on the earth and daughters were born to them,
References for Genesis 6:1
the sons of God saw that the daughters of man were beautiful, and they took any they chose as wives for themselves.
References for Genesis 6:2
And the Lord said, "My Spirit will not remain with mankind forever, because they are corrupt. Their days will be 120 years."
References for Genesis 6:3
The Nephilim were on the earth both in those days and afterwards, when the sons of God came to the daughters of man, who bore children to them. They were the powerful men of old, the famous men.
References for Genesis 6:4
When the Lord saw that man's wickedness was widespread on the earth and that every scheme his mind thought of was nothing but evil all the time,
References for Genesis 6:5
the Lord regretted that He had made man on the earth, and He was grieved in His heart.
Then the Lord said, "I will wipe off the face of the earth: man, whom I created, together with the animals, creatures that crawl, and birds of the sky-for I regret that I made them."
Noah, however, found favor in the eyes of the Lord.