Abraham and Sarah were old and advancing in years; Sarah had long since passed menopause.)

Now Abraham was old, well advanced in years, and the Lord had blessed him in everything.

God blessed them and said, “Be fruitful and multiply and fill the water in the seas, and let the birds multiply on the earth.”

The Nephilim were on the earth in those days (and also after this) when the sons of God were having sexual relations with the daughters of humankind, who gave birth to their children. They were the mighty heroes of old, the famous men.