Genesis 6:4-6

The Nephilim were on the earth in those days and also later. That was when the sons of God had physical relations with the daughters of men. These women gave birth to children, who became famous. They were the mighty warriors of long ago. The Lord saw that the human beings on the earth were very wicked. He also saw that their thoughts were only about evil all the time. The Lord was sorry he had made human beings on the earth. His heart was filled with pain.