Genesis 5:25-6:6

When Methuselah had lived 187 years, he begot Lamech. After the birth of Lamech, Methuselah lived 782 years and begot sons and daughters. All the days of Methuselah came to 969 years; then he died. When Lamech had lived 182 years, he begot a son. And he named him Noah, saying, "This one will provide us relief from our work and from the toil of our hands, out of the very soil which the Lord placed under a curse." After the birth of Noah, Lamech lived 595 years and begot sons and daughters. All the days of Lamech came to 777 years; then he died. When Noah had lived 500 years, Noah begot Shem, Ham, and Japheth. When men began to increase on earth and daughters were born to them, the divine beings saw how beautiful the daughters of men were and took wives from among those that pleased them. The Lord said, "My breath shall not abide in man forever, since he too is flesh; let the days allowed him be one hundred and twenty years." It was then, and later too, that the Nephilim appeared on earth--when the divine beings cohabited with the daughters of men, who bore them offspring. They were the heroes of old, the men of renown. The Lord saw how great was man's wickedness on earth, and how every plan devised by his mind was nothing but evil all the time. And the Lord regretted that He had made man on earth, and His heart was saddened. The Lord said, "I will blot out from the earth the men whom I created--men together with beasts, creeping things, and birds of the sky; for I regret that I made them." But Noah found favor with the Lord.