“By this simple literary stroke the author at once caught the spirit of ancient paganism and suggested darkly the satanic shapes that formed the background of the human revolt against the King of Kings. For these “sons of the god” were of all the seed of the serpent most like their father” (Kline, p. 192)
also, Reading the words of Genesis 6:2, “the sons of God (בְנֵי-הָאֱלֹהִים, bene elohim) saw the daughters of men,” i found this The Sons of God" in Gen. 6.2, 4. It is only by the Divine specific act of creation that any created being can be called “a son of God.” For that which is “born of the flesh is flesh.” God is spirit and that which is “born of the Spirit is spirit” (John 3.6). Hence Adam is called a “son of God” in Luke 3.38. Those “in Christ” having the “new nature” which is by the direct creation of God (2 Cor. 5.17; Eph. 2.10) can be, and are called “sons of God” (John 1.13; Rom. 8.14, 15; 1 John 3.1).
another possible view is that “the sons of God” were the sons of pre-Flood rulers or magistrates. This belief became the standard explanation of rabbinical Judaism after Rabbi Simeon ben Yochai pronounced a curse in the second century CE upon those Jews who believed the common teaching that the angels were responsible for the nephilim. This interpretation was advocated by two of the most respected Jewish sages of the Middle Ages, Rabbi Shlomo Yitzchaki (Rashi) and Rabbi Moshe ben Nachman (Nachmanides), and became the standard explanation of rabbinical Judaism. However, it is not widely accepted by modern scholars.
Josephus believed and recorded that “the sons of God” mentioned in Genesis 6 were fallen angels. As Whitson’s footnote acknowledges, this belief was standard in the ancient world.
Another well-known first century CE Jewish writer, Philo of Alexandria, shared Josephus’ views on this topic. In his work “On the Giants,” Philo wrote:
"And when the angels of God saw the daughters of men that they were beautiful, they took unto themselves wives of all them whom they chose." Those beings, whom other philosophers call demons, Moses usually calls angels . . . (p. 152, The Works of Philo, "On the Giants," translated by C.D. Yonge)
The Book of Enoch (also called I Enoch) also holds to a similar view The Genesis Apocryphon, one of the texts uncovered among the Dead Sea Scrolls, also contains references to the angels interbreeding with human women. In this text, a conversation between Lamech, the father of Noah, and his wife Bathenosh is detailed. Lamech questions his wife because he thinks that the conception of Noah was due to either an angel or one of their offspring, a nephilim. The Book of Enoch, the Book of Jubilees, and the Genesis Apocryphon all clearly show that the common understanding at the time of Yeshua was that the fallen host had committed fornication with women in the period before the Flood.
As stated previously, many early Christian writers accepted the story told in Enoch as fact. Let’s examine the writings of two of them, beginning with Justin Martyr, who lived from 110 CE to 165 CE.
another similar passage is also found in the pseudepigraphic Book of Jubilees:Here is what he had to say in chapter 5 of his Second Apology, entitled "“How the Angels Transgressed”:
God, when He had made the whole world, and subjected things earthly to man, and arranged the heavenly elements for the increase of fruits and rotation of the seasons, and appointed this divine law – for these things also He evidently made for man – committed the care of men and of all things under heaven to angels whom He appointed over them. But the angels transgressed this appointment, and were captivated by love of women, and begat children who are those that are called demons; and besides, they afterwards subdued the human race to themselves, partly by magical writings, and partly by fears and punishments they occasioned, and partly by teaching them to offer sacrifices, and incense, and libations, of which things they stood in need after they enslaved by lustful passions; and among men they sowed murders, wars, adulteries, intemperate needs, and all wickedness. . . . (p. 363, vol. 1, The Ante-Nicene Fathers)
Now let’s examine chapter 3, “The Worship of Demons,” from The Instructions of Commodianus, a North-African bishop who lived about 240 CE:
When Almighty God, to beautify the nature of the world, willed that that earth should be visited by angels, when they were sent down they despised His laws. Such was the beauty of women, that it turned them aside; so that, being contaminated, they could not return to heaven. Rebels from God, they uttered words against Him. Then the Highest uttered His judgment against them; and from their seed giants are said to have been born. By them arts were made known in the earth, and they taught the dyeing of wool, and everything which is done; and to them, when they died, men erected images. But the Almighty, because they were of an evil seed, did not approve that, when dead, they should be brought back from death. Whence wandering they now subvert many bodies, and it is such as these especially that ye this day worship and pray to as gods. (p. 435, vol. 4, The Ante-Nicene Fathers)