KEY TEXT: Genesis 6:1-8 When man began to multiply on the face of the land and daughters were born to them, the sons of God saw that the daughters of man were attractive. And they took as their wives any they chose. Then the Lord said, "My Spirit shall not abide in man forever, for he is flesh: his days shall be 120 years." The Nephilim were on the earth in those days, and also afterward, when the sons of God came in to the daughters of man and they bore children to them. These were the mighty men who were of old, the men of renown. The Lord saw that the wickedness of man was great in the earth, and that every intention of the thoughts of his heart was only evil continually. And the Lord was sorry that he had made man on the earth, and it grieved him to his heart. So the Lord said, "I will blot out man whom I have created from the face of the land, man and animals and creeping things and birds of the heavens, for I am sorry that I have made them." But Noah found favor in the eyes of the Lord.
KEY THOT: There are two basic interpretations of the expression "sons of God" (Hebrew: bene ha elohim). One is that it refers to the godly offspring of Seth who intermarried with ungodly daughters of Cain. In other words, they were humans that were corrupted through sexual immorality, producing a strange human species known as the Nephilim. The main argument for this view is based on Jesus' statement in Matthew 22:30 that angels do not marry: "For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven." But these refer to the angels that are still in heaven, not fallen angels.
The second view is that the sons of God refer to fallen angels. The main argument for this view are Job 1:6 and 2:1 which use bene ha elohim to refer to angels who came before God's throne with Satan: "Now there was a day when the sons of God [bene ha elohim] came to present themselves before the Lord, and Satan also came among them." A third possible view (not held by the early church fathers) seeks to integrate the first two views. It proposes that fallen angels took possession of humans and had sexual relations with women through these demonized males.
That angels did have sexual relations with women may be hinted in Jude 6-7: "And the angels who did not stay within their own position of authority, but left their proper dwelling, he has kept in eternal chains under gloomy darkness until the judgment of the great day— just as Sodom and Gomorrah and the surrounding cities, which likewise indulged in sexual immorality and pursued unnatural desire, serve as an example by undergoing a punishment of eternal fire."
Personally, I am inclined to take the second view (commonly held by the early church fathers, Jewish interpreters and also reflected in the Greek OT, LXX), viz., that the sons of God are fallen angels that took on human forms to have sexual relations with women. The resulting offspring were the Nephilim who were described as "mighty men...men of reknown", suggesting a cross-bred superhumans And it was because of this great wickedness that the Lord decided to wipe the human race off from face of the earth in a flood. This is noted in Genesis 6:5-7, "Then the Lord saw that the wickedness of man was great in the earth, and that every intent of the thoughts of his heart was only evil continually. And the Lord was sorry that He had made man on the earth, and He was grieved in His heart. So the Lord said, "I will destroy man whom I have created from the face of the earth, both man and beast, creeping thing and birds of the air, for I am sorry that I have made them." Such stories can also found in myths of many ancient cultures. According to Jude 6-7, these angels are so vile they are locked up in chains in the Abyss so that they can no longer interact with humans.
The point of Genesis 6:1-8 was to provide the background for the reason why God had to destroy all human life on earth in the Flood. Only Noah found favour with God because the spiritual and moral corruption was so widespread that practically no one was free from evil.
We are now witnessing in these last days the return of such spiritual and moral corruption of the human race through vile demonic doctrines that seek to normalize sexual perversion like homosexuality, paedophilia, bestiality--even now incest. As believers, we must be on guard against the demonic spirits that are now spreading lies that "love" can justify any act, as long as it doesn't harm others.
Sadly, some believers are being likewise deceived. And their destiny may not be heaven, but the "punishment of eternal fire" (Jude 7).
Abba-Father, You have warned us in Scripture against the occult and demonic infiltration of human society. We are seeing today evidence of this infiltration of sexual immorality through demonic spirits. Grant Your people discerning of spirit to identify such spirits to cast them out of the Church of Jesus Christ. Amen.