‘And the sons of God saw that the daughters of men were fair, and took to wife such of them as they chose.'
In the Old Testament the term the ‘sons of God' (bene ha-elohim) always refers to heavenly beings (Job 1:6 and context; 38:7; Psalms 29:1; Psalms 89:7; Daniel 3:25; Deuteronomy 32:8 in the LXX; see also Jude 1:6-7; 1 Peter 3:19-20, and 2 Peter 2:4-6).
But if we take that meaning here we need not think of it as a crude representation of heavenly beings becoming men to slake their desires. It is true that they thought these women were ‘desirable', but it could have been for another reason, and that was because they were seen as presenting a means by which these evil ‘angels' could interfere directly in the affairs of men, take over human bodies and possibly even regain acceptability. The thought would thus be more of occult practises, and especially demonic marriages rather than of sex. The Bible regularly covers up gross sin by euphemisms, and this is one such case. The writer is describing it in folksy terms as though it were normal marriage. But it is describing demon possession of a most dreadful kind.
“Saw that the daughters of men were fair.” The word for ‘fair' means more literally ‘good, useful' for some purpose. Thus they saw them as suitable for their purposes.
We cannot, however, avoid the thought that the women were very willing. They were not just helpless tools. This interest in the occult was clearly rampant almost right from the beginning (so Genesis 6:1 suggests), with the result that the evil angels were able to take their pick. Thus by opening themselves to occult practises of an extreme kind, and especially to voluntary demon possession, these women, presumably the large majority, were being ‘bound' to these ‘fallen angels'. Whereas Eve had unknowingly succumbed to temptation by the powers of evil, these women glory in it and throw themselves fully into it.
There are a number of other alternatives suggested for the significance of the term ‘the sons of God' which we will now consider.
1). That ‘the sons of God' represent the so-called godly line of Seth and ‘the daughters of men' represent the cursed line of Cain, (or indeed the daughters of other sons of Adam). In favour of this is that it directly follows the genealogies of Cain and from Adam to Noah.
But there is no reason why we should think that all the line of Seth were godly. Certainly, many of their ‘sons and daughters' must have had descendants who perished in the flood. Nor is there any reason why they would be seen above all as especially producing ‘mighty men' and ‘men of renown'. Indeed Lamech appears to be a simple son of the soil (5:28). Nor does it explain why they should be called ‘nephilim' (compare Numbers 13:33), nor why such men should be able to have their pick of women anywhere. The fact is that by the time of the Flood the vast majority of the line of Seth were anything but godly and were also destroyed in the Flood. Nor is this concept of a ‘godly' line being called the ‘sons of God' (bene ha elohim) found in the Old Testament, whereas the phrase is used otherwise.
In favour could be said to be the fact that God calls Israel ‘my firstborn son' (Exodus 4:22). But this rather contrasts Israel as a whole, as adopted by God, with the ‘divine' Pharaoh's son and is not really parallel with this.
A better parallel is perhaps ‘you are the sons of Yahweh your God' (Deuteronomy 14:1). But again this refers to the special position of the children of Israel as those who have been delivered from Egypt, demonstrating their unique position with God. They are adopted by Him as His own.
Both these phrases are very different from the phrase the ‘sons of the elohim' where the very nature of elohim, heavenly beings, is usually in mind. Besides why are they not called the ‘sons of Yahweh' here, as Moses does, if the godly line were meant? It was Yahweh they worshipped (Genesis 4:26). It is Yahweh which is the name connected with the covenant, not Elohim, and the name Yahweh is used in the passage.
And if the line of Seth were godly enough to be called ‘the sons of God', why did they marry the daughters of men, deluded by their charms? Surely if the writer had this in mind he would have included a reference to them as ‘sons of God' somewhere in the genealogy. Yet Seth was specifically described as being the image and likeness of Adam, not the image and likeness of God.
2). That ‘the sons of God' are Neanderthals, or a similar species, appearing as from nowhere and being seen as supernatural beings because of their size and therefore being given this name in popular parlance, and they, or their children, being also called Nephilim. It is possible to imagine the effect produced on the population if a considerable group of these huge beings arrived and forced themselves on the ‘daughters of men', with no one daring to offer resistance.
The daughters of men are then seen as intermarrying with them, producing huge offspring. This is feasible and would tie in with Numbers 13:33, the point being that the huge men there were seen as somehow connected with a similar situation. Nephilim might be thus seen as a term for the progeny of such alliances.
Such alliances might well have been seen by the people and the writer as unholy alliances bringing God's anger down on the them. One of the points later brought out is the violence which preceded the flood which might well have resulted from such an ‘invasion'.
3). That the sons of God (sons of the gods) represent royal personages. These often set themselves up as being divine or semi-divine, seeing themselves as sons of their gods. Thus the idea may be that they exalted themselves and set up their harems, and took whom they would, whether willing or not. The rare word Nephilim is then accepted as meaning powerful men, then men of renown. The idea is then that the writer sees this as resulting in multiple marriages, a further downward step in man's behaviour.
All these theories, except perhaps 2 where they were thought to be heavenly beings, founder on the fact that the ‘sons of elohim' (those of the nature of the elohim) is a recognised form for supernatural beings and suggests exactly that, but some nevertheless prefer them to our suggested interpretation.