And they were in all two hundred; who descended in the days of Jared on the summit of Mount Hermon, and they called it Mount Hermon, because they had sworn and bound themselves by mutual imprecations upon it ...
All early sources refer to the "sons of heaven" as angels.From the third century BCE onwards, references are found in the Enochic literature, the Dead Sea Scrolls (the Genesis Apocryphon, the Damascus Document, 4Q180), Jubilees, the Testament of Reuben, 2 Baruch, Josephus, and the book of Jude (compare with 2 Peter 2).According to these texts, the fallen angels who begat the Nephilim were cast into Tartarus (2 Peter 2:4, Jude 1:6) (Greek Enoch 20:2), a place of "total darkness".However, Jubilees also states that God granted ten percent of the disembodied spirits of the Nephilim to remain after the flood, as demons, to try to lead the human race astray until the final Judgment.This line of interpretation finds additional support in the text of Genesis 6:4 which juxtaposes the sons of God (male gender, divine nature) with the daughters of men (female gender, human nature).
From this parallelism it could be inferred that the sons of God are understood as some superhuman beings.
Ronald Hendel states that it is a passive form "ones who have fallen", grammatically analogous to The Nephilim were in the earth in those days, and also after that, when the sons of God came in unto the daughters of men, and they bore children to them; the same were the mighty men that were of old, the men of renown.
The nature of the Nephilim is complicated by the ambiguity of Genesis 6:4, which leaves it unclear whether they are the "sons of God" or their offspring who are the "mighty men of old, men of renown".
The New American Bible commentary draws a parallel to the Epistle of Jude and the statements set forth in Genesis, suggesting that the Epistle refers implicitly to the paternity of Nephilim as heavenly beings who came to earth and had sexual intercourse with women.; or "sons of the gods") is used twice outside of Genesis chapter 6, in the Book of Job (1:6 and 2:1) where the phrase explicitly references angels.
The Septuagint manuscript Codex Alexandrinus reading of Genesis 6:2 renders this phrase as "the angels of God" while Codex Vaticanus reads "sons".
Samyaza, an angel of high rank, is described as leading a rebel sect of angels in a descent to earth to have sexual intercourse with human females: And it came to pass when the children of men had multiplied that in those days were born unto them beautiful and comely daughters.