So on the topic of there after and the Nephilim. So God told Abraham that his descendants would be captives in Egypt for 400 years. So as soon as Jacob and his extended family go to Egypt the Nephilim begin to appear in Canan and populate the area as a future deterrent to the people of God (descendants of Abraham). So by the time Moses leads the people out of Egypt and they approach the "Promised Land" the spies meet or see the Nephilim. Just another attempt by Satan to destroy the line of the future Messiah. These are my thoughts after years of thinking about why they suddenly appeared again.