sons of God
Some hold that these "sons of God" were the "angels which kept not their first estate" (Jude 1:6). It is asserted that the title is in the Old Testament exclusively used of angels. But this is an error (Isaiah 43:6). Angels are spoken of in a sexless way. No female angels are mentioned in Scripture, and we are expressly told that marriage is unknown among angels. (Matthew 22:30).
The uniform Hebrew and Christian interpretation has been that verse (Genesis 6:2) marks the breaking down of the separation between the godly line of Seth and the godless line of Cain, and so the failure of the testimony to Jehovah committed to the line of Seth (Genesis 4:26). For apostasy there is no remedy but judgment; (Isaiah 1:2-7); (Isaiah 1:24); (Isaiah 1:25); (Hebrews 6:4-8); (Hebrews 10:26-31). Noah, "a preacher of righteousness," is given 120 years, but he won no convert, and the judgment predicted by his great-grandfather fell; (Jude 1:14); (Jude 1:15); (Genesis 7:11).