Genesis 6: “the sons of God and daughters of men”.
An Old Testament theme, where the Nephilim were seen as the offspring of sexual relationships between the sons of God and daughters of men.
There is much debate as to the identity of the “sons of God,” possibly fallen angels who mated with human females or possessed human males who then mated with human females. These unions resulted in offspring, the Nephilim, who were described, somewhat strangely as “heroes of old, men of renown”. If as described in these latter glowing terms, is there a touch of Gnostics philosophy here, incorporating a “spark of the divine” into sections of mankind?
If, however, we are talking of fallen angels, was the motivation one of attempting to pollute the human bloodline in order to prevent the coming of the Messiah.
God had promised that the Messiah would one day crush the head of the serpent, Satan (Genesis 3:15).
The fallen angels in Genesis 6 thus were possibly attempting to prevent this and make it impossible for a sinless “seed of the woman” to be born.
The Nephilim were apparently a race of giants, which combined with their fallen angel status made them a formidable force of evil. Their great size and power presumably came from the mixture of demonic “DNA” with human genetics. Thus, the progeny of a union between the “sons of God” and the daughters of men” was of such a character as to indicate a super-human union.
What then followed, it could be argued, was that the Nephilim were one of the primary reasons for the great flood in Noah’s time.
“The Lord saw how great man’s wickedness on the earth had become, and that every inclination of the thoughts of his heart was only evil all the time. The Lord was grieved that he had made man on the earth, and his heart was filled with pain.”
So, the Lord said, ‘I will wipe mankind, whom I have created, from the face of the earth—men and animals, and creatures that move along the ground, and birds of the air—for I am grieved that I have made them’”
What followed was the flood of the entire earth, killing everyone and everything other than: Noah, his family, and the animals on the ark.
All else perished, including one would suppose the Nephilim.
Or is there a twist in the tale; that it is possible that some traits of the Nephilim were passed on through the heredity of one of Noah’s daughters-in-law?
What we must keep in mind is that originally the term “sons of God” denoted beings that were brought into existence by the creative act of God.
Such were the angels, and in the Old Testament the title refers to angels.
Men are not “sons” until they are redeemed and born again in the New Testament sense.
The angels in heaven do not marry, nor are given in marriage. But, the “sons of God” in Geneses 6:1-4 were no longer in heaven, having left their own place, and came seeking after an unapproved alliance with the daughters of men.
Finally, there is a school of thought that thinks in terms of modernist angels; spiritual placeholders, reminders that something has been lost, even if it is difficult to know exactly what this is. Unrealized manhood perhaps?