“The mysterious identity of the sons of God continues to humble expositors.” Although both sides agree that the main point of these verses is an attack on the seed of the woman (Gen 3:16), we do get there different ways.
The Lord said there would be conflict between the woman’s seed and Satan’s. Cain, “of the wicked one” (1Jn 3:12), represents the diabolic camp.
Genesis 4:16-5:32 is highly structured. The families of Cain and Seth are not recorded in chronological order. Moses records the whole Cainite line before reverting back to Seth. The apples don’t fall far from the tree, as Cain’s descendants bear the image of their father, culminating in Lamech, who starts polygamy and murders a man (4:23). This is Satan’s line.
It is only after this that Moses mentions Adam again (4:25-5:3) – the family head, son of God (Luk 3:38) and man of faith (Adam moved in faith by “[knowing] his wife again” – 1:28; 3:20; 4:25). The household follow the head – the line recorded in chapter 5 is a godly line. Seth is appointed instead of Abel; thus, the seed of the woman continues.
The line of Cain and Seth are placed side by side by way of contrast.
Although Adam had other sons and daughters (5:4), Moses doesn’t focus on them, but instead re-states that Adam was made in the “likeness of God” (5:1); and this “likeness” transferred exclusively to Seth (not Cain) as the son “in [Adam’s] likeness, after his image” (5:3). This is more than a repetition of the creation account (1:26). Even Cain bore the imago dei in a general sense. Moses is using sonship, not creation language, exclusively about the Sethite line. This line bore the name of God, represented Him (image) and morally resembled Him (likeness).
The idea of sonship was easily understood by the original readership (Israel). They were told, “Ye are the sons of the living God” (Hos 1:10). They saw themselves as God’s representatives on earth (Exo 4:22) and would have seen the Sethite line as God’s representatives in the antediluvian world. Israel’s conception of sonship here was human, not angelic.
The Sons of God
With this in the background, the text now mentions “the sons of God” (6:2). We have had plenty of clues about who Moses is thinking of. Angels are foreign to the context. Every other time Moses mentions angels in the Pentateuch, he makes clear that they are angels. Since context determines meaning, and the nearer context of the Pentateuch takes precedence over the further context of Job, angels are precluded. In the Pentateuch, “sons of God” are men; Israel was referred to as “sons of Jehovah your God” (Deu 14:1 JND). Note also these phrases: “Israel is my son” (Exo 4:22), “His sons” (Deu 32:5 YLT), “Is not He thy father” (v6 YLT). These verses show that a father-son relationship existed between men and God. It was Israel in the Mosaic era, and the Sethite line in the antediluvian era.
If the sons of God are angels, it would seem strange to call demons (who had fallen with Satan) by that title. Neither Satan nor demons are called sons of God. Satan is distinguished from the sons of God when he comes among them in Job (Job 1:6; 2:1). The singing of the sons of God in creation (Job 38:7) is likely before Lucifer fell. Some argue that angels taking human wives was a new and separate fall about 2000 years after Lucifer’s. This argument is difficult since Satan and his host seem to have fallen together (Rev 12:4).
The Daughters of Men
The contrasting lines of Seth and Cain meet after the juxtaposition of the previous chapters, when “the sons of God saw the daughters of men” and intermarry (6:2). The sons of God are tempted in the same way as Eve (3:6); they “saw” something “fair” and they “took.” This is how men – not angels – are tempted (cf. Jos 7:21; 2Sa 11:2,4; 1Jn 2:16). Satan worked through violence to kill Abel, and now works through corruption.
In the nearer context of the Pentateuch, this interpretation makes better sense. The Patriarchs normally married within their own families (Gen 20:12; 24:15; 29:12) to protect the promised seed. It was profane men like Esau who married “daughters of the land … daughters of Canaan” (27:46; 28:6). Numerous times in Genesis, the seed comes close to being corrupted, whether through Pharaoh (12:19), Abimelech (20:3; 26:10) or the defilement of Dinah (34:13). The suggestion of Shechem would have horrified the readership of Genesis: “Make ye marriages with us … take our daughters unto you … we will become one people” (34:9,16). Moreover, intermarriage between the godly and ungodly (whether Sethites here or Israel later) was a constant problem: at Baal-Peor, when Israel “began to commit whoredom with the daughters of Moab” (Num 25:1); after the death of Joshua, when “the sons of Israel … take their [Canaanite] daughters to them for wives” (Jdg 3:5-6 YLT); or in the post-exilic period. Ezra is very specific: “The people of Israel … have taken … daughters … so that the holy seed have mingled themselves with the people of those lands” (Ezr 9:1-2). This lesson is completely obsolete if the sons of God are angels.
This point is not a relic of history either; following strange women in the physical or digital world leads to hell (Pro 7:5,27).
It is noteworthy that these men took “wives.” Those who quote Jude run into difficulty here – “Sodom and Gomorrah, and the cities around them, in like manner to these, [gave] themselves to whoredom” (Jud 7 YLT). Able grammarians suggest “in like manner to these” references the ungodly men of the epistle (v4), not the angels of the preceding verse (v6). Jude does this repeatedly (vv8,10,12,14,16,19). Genesis 6 mentions intermarriage and not the fornication highlighted by Jude. The Lord Himself mentions a proliferation of marriage (not fornication, Luk 17:27). The godly line had become like ungodly Lamech in multiplying wives (Gen 4:19). This is why the flood came; “the earth also was corrupt before God” (6:11). The godly line also became violent like Lamech (4:23), resulting in “the earth [being] filled with violence” (6:11).
The sin of the angels in Jude is that they did not keep “their own position of authority, but left their proper dwelling” (v6 ESV). Their ring leader, Satan, did not keep his position of authority when he grasped for the throne of God (Isa 14:14), and as a result he was cast out of his proper dwelling – heaven (Eze 28:16). In a similar way, the angels in Jude repeated the sin of Satan – he drew them after him (Rev 12:4).
Adam, Giants and Mighty Men
The word “man” (adam) dominates the early verses of Genesis 6 (eight times in seven verses). The corruption of marriage lands firmly at man’s door. The statement that “he is [corrupt] flesh” (6:3) condemns man, not angels.
The identity of the giants (Nephilim) is grammatically difficult, but not so hard in the wider context of the Pentateuch. Giants existed “in those days” (i.e., the antediluvian era). “Also after that” is best put in parentheses, and is an editorial insertion by Moses to say that the Nephilim existed after the flood. He does this for the benefit of his readership (Israel), since their neighbours, the sons of Anak, came from the giants (Num 13:33). The Anakim were like the Nephilim – “a people great and tall,” and violent; “Who can stand before … Anak?” (Deu 9:2). Since the Nephilim existed before and after the flood, this excludes the idea of demi-god offspring. Israel learned that just as God had dealt with giants in judgement in Noah’s day, He would do the same in their day (Jos 15:14).
There are four distinct, co-existent parties here: giants, sons of God, daughters of men and men of renown (Gen 6:4). It is not surprising that human marriages produced human offspring. The words “bare … mighty men [gibor] … men of renown [enosh]” always refer to human beings in the Pentateuch. “Mighty men” are often associated with military men (10:8,9; Jos 1:14; 1Sa 9:1; 17:51). If the intermarrying resulted in corruption, the offspring resulted in violence. This warrior class is juxtaposed with the giants, since the two races battled together (the wider context of the Pentateuch shows this; see also Jos 15:14).
“Men of name” (YLT) once had a father who called on the “name of the Lord” (4:26), but the Sethites now lived for their own glory. In pride they fought to establish their name in the world. “Men of name” is used of Korah and his followers (Num 16:2), who, like their antediluvian counterparts, tried to establish their own reputation. The original readership would have seen the parallel.
There is not the slightest indication in these four distinct groups of angelic offspring. Angels cannot marry (Mar 12:25) and produce hybrid offspring. Angels are fundamentally spirits (Heb 1:14) who do not have flesh and bone (Luk 24:39). Although they appear like men, it is impossible for them to cross the God-ordained species barrier and procreate with humans (1Co 15:39-44). The sons of God are Sethites, not angels.
 Kenneth A. Mathews, Genesis 1–11:26, Vol 1A, The New American Commentary (Nashville, TN: Broadman & Holman Publishers, 1996), 332.
 Bible quotations in this article are from the KJV unless otherwise noted.
 Mathews, 331.
 Keil and Delitzsch. See also Michael A. Kruger, “Τούτοις in Jude:7,” Neotestamentica – Journal of the New Testament Society of Southern Africa, Vol. 27, No. 1.