According to evidence from the Bible, the “sons of God” (BENEH HA ELOHIM) were disobedient angels who rejected their proper station in the spirit realm and lusted after human women and power. The product of their interspecies cohabitation evidently resulted in genetic hybrids; large misshapen children called Nephilim.
Many Bible translators understand these “sons of God” as angels and show this in there renderings:
"supernatural beings" TEV1, CEV
"heavenly beings" TEV2, New Jewish P.S.,
"beings from the spirit world" Living Bible
"angels" LXX Codex Alexandrinus, Moffatt
The conclusion that these sons of God were actually wicked angels who materialized fleshly bodies comes from several lines of Scriptural evidence.
First, the phrase “sons of God” occurs only five times in the bible. The three times in Job clearly refer to angels. Job 1:6; 2:1; 38:7. The LXX has all three rendered as "Angels" not as "Sons of God."
In Gen. 6:2 the Alexandrian text has Angels. So it seems that the Jews understood that the "Sons of God" were angels.
While many commentators hold that these ‘sons of God' were themselves human, there is nothing to support the view that human intermarriage were responsible for the birth of "mighty ones" as mentioned in Ge 6:4.
(The following largely quoted from “Insight on the Scriptures”)
“If these "sons of the true God" were merely men, the question arises, Why were their offspring "men of fame" more than those of the wicked, or of faithful Noah? Also, the question might be asked, Why mention their marriage to the daughters of men as something special? Marriage and childbearing had been taking place for more than 1,500 years.
"On the other hand, there is an explanation that finds corroborating evidence in the Scriptures. The expression "sons of the true God" occurs at Job 1:6, and is obviously spirit sons of God assembled in God's presence. (Job 1:7; 2:1, 2.) Again at Job 38:4-7 and at Ps 89:6 "the sons of God" are definitely heavenly creatures, not earthlings.
"Supporting this are the apostle Peter's references to "the angels that sinned," mentioned in connection with Noah's time (2Pe 2:4, 5), as well as Jude's statement concerning "the angels that did not keep their original position but forsook their own proper dwelling place." (Jd 6 cf. 1Pe 3:19, 20) If it is denied that "the sons of the true God" of Gen 6:2-4 were spirit creatures, then these statements by the Christian writers become enigmatic, with nothing to explain the manner in which this angelic disobedience took place, or its actual relation to Noah's time.
"Angels definitely did materialize human bodies, even eating and drinking. (Ge 18:1-22; 19:1-3) It should be noted that Jude's reference to angels as not keeping their original position and to them as forsaking their "proper dwelling place" (certainly here referring to an abandoning of the spirit realm) is immediately followed by the statement: "So too Sodom and Gomorrah, after they in the same manner as the foregoing ones had committed fornication excessively and gone out after flesh for unnatural use, are placed before us as a warning example." (Jd 6, 7) Thus, the combined weight of the Scriptural evidence points to angelic deviation, the performance of acts contrary to their spirit nature, occurring in the days of Noah. There seems to be no valid reason, then, for doubting that the ‘sons of God' of Gen 6:2-4 were angelic sons."
We recognize that the Nephilim were most likely the hybrid human children of these wicked angels because they are described as "ANSHEI-HASHEM" which means literally, "*men* of fame."
The name "Nephilim," meaning "Fellers," denotes individuals who caused others to fall. Together, they whipped up intolerable wickedness on earth.
The Nephilim were all destroyed at the flood since ONLY Noah and his three sons with their wives survived.
“Wicked angels did not regain their lofty original position after the flood, according to Jude 6 (1Pe 3:19, 20). So it is in this condition of dense spiritual darkness that they must now confine their operations. (2Pe 2:4)
“Since the angelic ‘sons of God’ who came to earth and assumed human bodies in Noah’s day couldn’t be destroyed by the flood and they had forsaken heaven, they were apparently put into a prison-like state--restricted in bonds--which evidently included not being allowed ever again go contrary to God's purpose by materializing and having relations with humans.” Though they still have great power and influence over men, even having the ability to enter into and possess humans and animals, and the facts show that they also use inanimate things such as fetishes, and charms.—Mt 12:43-45; Lu 8:27-33"
As a side note, Christians should pay close attention to the date of the flood and the modern celebration of Halloween.
The writer J. Garner points out that Halloween celebrations can be traced back to the ancient destruction of all of Satan’s human followers, as well as the hybrid sons of fallen angels:
"Perhaps in no other `Christianized' celebration does Satan so blatantly honor himself and memorialize his war dead. Cultures the world over have festivals for the dead, `held by all on or about the very day on which, according to the Mosaic account, the Deluge took place, viz., the 17th day of the second month—the month corresponding with our Nov."—The Worship of the Dead
There is no holiday as disgusting as Halloween. Everything associated with it, violence, extortion, and living-death is demonic. The very date is a memorial of Satan and the Demons' "children" who were killed at the flood. Should we mourn those killed by god for their violent, immoral ways?
"Witches find that coven feeling on Halloween. All the ghosts, skeletons and zombies out trick-or-treating are celebrating pre-Christian traditions [of witchcraft]. Basically, people are keeping alive and celebrating in our way. Victory through assimilation!" —News article quoting a witch
A USA Today article quoted witch Bryan Jordan as saying, "[Christians] don't realize it, but they're celebrating our holiday with us... We like it."
True Christian parents would not want our children imitating these sinister rituals, reenacting and memorializing Satan’s dead loved ones.
Answers to “additional details”:
2. As a rule, angels do not marry. We can easily reconcile this general statement by Jesus with common sense. When we are speaking of spirit beings in their *normal* and proper position and realm, and obedient to their creator’s purpose, it is accurate to say angels do not marry. However, the Scriptures state that these angelic “sons of god” “did not keep their original position but forsook their own proper dwelling-place (Jude 6). So, we cannot demand that a general statement nullifies what happened in a specific incident. For example I can correctly say “Dogs do not mate with cats,” but does that negate the fact that in abnormal situations I’ve witnessed that? Generally it’s true, but does not apply to the specific anomalies.
3. The account does not give us many details, which is why we must examine similar accounts. The fact is that angels did, in fact, materialize physical bodies in other occurrences, so it is acceptable to inductively link that fact with this account.
4. Since the Hebrew language did not incorporate our idea of “tense” this verse is debated by Hebrew scholars; is it speaking of them existing *before* the “sons of God” came, or is it referring to the result? The ISBE has a very good writeup, and I agree with “Hastings Dict. of the Bible”: “‘The Nephilim were in the earth in those days, and also afterward, forasmuch as the sons of God used to go in to the daughters of man, and they bare them children’. The connective ‘forasmuch as’ articulates the statement better than the word ‘when’, used in the English versions. It is not explicitly said that the Nephillm were the heroes borne by women to the sons of God, and some scholars have held that they were not; but this writer certainly meant that they were, for otherwise it is impossible to account for his mentioning them at all. There is much here not easy to understand.”
The clauses "when the sons of the true God continued to have relations..." and “after that” refers to the time just mentioned. The Nephilim existed in "those days" that God first condemned them and "after that" declaration of judgement until God carried it out at the flood. This understanding is confirmed in that the Nephilim were all destroyed at the flood since ONLY Noah and his three sons with their wives survived.
5. The mis-translation “giants” arose due to the uncertainty of the root words and due to influence of the Num.13:33 account. “Giants—The term in Hebrew implies not so much the idea of great stature as of reckless ferocity, impious and daring characters, who spread devastation and carnage far and wide.”--JFB