The interpretation of Genesis 6:1–4 is difficult and controversial. The debate centers on the interpretation of the phrase “sons of God.” Who are they? The crucial question concerns whether the phrase refers to human beings or to spiritual beings (demons).

The full passage reads:

When man began to multiply on the face of the land and daughters were born to them, the sons of God saw that the daughters of man were attractive. And they took as their wives any they chose. Then the Lord said, “My Spirit shall not abide in man forever, for he is flesh: his days shall be 120 years.” The Nephilim were on the earth in those days, and also afterward, when the sons of God came in to the daughters of man and they bore children to them. These were the mighty men who were of old, the men of renown.

Option 1: Sons of God = Sons of Seth

One view understands the “sons of God” as descendants of Seth. In this interpretation, Seth’s godly descendants were intoxicated by the beauty of women descended from Cain, thus marrying those who’d rejected God and leading to greater wickedness.

The strongest evidence for this position is found in Genesis 4–5, which describe two lines of descent from Adam: one through Cain and the other through Seth. In the Old Testament, God’s covenant people are sometimes referred to as God’s sons (Deut. 14:1; Jer. 3:19), though the precise phrase “sons of God” is never used of them. If the Sethite view is correct, this could explain why God later forbade the Israelites from marrying Canaanite women (Ex. 34:16; Deut. 7:3).

Option 2: Sons of God = Fallen Angels

The oldest, and likely the most widely held, interpretation is that the “sons of God” are fallen angels (demons). This was the interpretation most favored in ancient Judaism and the early church (cf. 1 Pet. 3:19–20; 2 Pet. 2:4; Jude 6). The phrase “sons of God” is clearly used elsewhere of angelic hosts in God’s heavenly court (cf. Job 1:6; 2:1; 38:7). Moreover, the narrator seems to contrast “man” and “the daughters of man” with the “sons of God” in Genesis 6:1–2.

This position is not without difficulties, however, most substantial of which is the idea of fallen angels having physical relations with women. Scripture gives instances of angels engaging in human activities such as eating (Gen. 18:1–2, 8; 19:1, 5), but surely sexual intercourse is a step beyond! Jesus makes a similar point in Matthew 22:30: “For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven.”

Which Is Right?

Despite the obvious difficulties of the second interpretation, I believe the evidence points slightly in its favor, mainly because both Peter and Jude seem to have held to it.

In 1 Peter 3:18–22, Peter refers to spirits in prison because they disobeyed in Noah’s day (1 Pet. 3:19–20). Though disputed, the word “spirits” most likely refers to evil spirits (cf. Matt. 8:16; 12:45; Luke 4:36; 10:20; Acts 19:12–16). The connection of these spirits with Noah’s day points strongly to Genesis 6. That these “spirits in prison” are fallen angels is further confirmed by similar passages in 2 Peter and Jude.

In 2 Peter 2:4–10, for example, the apostle cites three Old Testament examples of God’s judgment as a warning to false teachers. First are the fallen angels who are chained and awaiting final judgment (2 Pet. 2:4). The second and third examples are the flood in Noah’s day (2 Pet. 2:5; cf. Gen. 6–8) and the destruction of Sodom and Gomorrah (2 Pet. 2:6; Gen. 19). Given that the second and third examples not only come from Genesis but are also listed in chronological order, it makes sense to see the first example as also coming from Genesis. (Genesis 6:1–4comes right before the flood narrative, after all.) Since angels are spiritual beings, Peter’s reference to their being “chained” refers not to physical chains, but rather to a limitation of their activity—presumably to prevent them from indulging in such wickedness again.

Jude, like Peter, provides three Old Testament examples of God’s judgment (Jude 5–7). Unlike Peter, he doesn’t mention the flood and doesn’t place them in chronological order. Still, Jude 6 parallels 2 Peter 2:4 and appears to be an allusion to Genesis 6:1–4. These angels demonstrated sinful pride by abandoning their position of authority and leaving their proper dwelling. They’re now being “kept in eternal chains” until the Day of Judgment. The comparison with the men of Sodom and Gomorrah in Jude 7 (“just as Sodom and Gomorrah . . . likewise indulged in sexual immorality and pursued unnatural desire”) implies that this was also the angels’ sin in Jude 6.

How Is This Possible?

Admittedly, these passages don’t provide a definitive answer as to how spiritual beings could have sexual relations with women. But in light of examples we see in the New Testament, it seems best to assume that these evil spirits took possession of the bodies of wicked men and used them for their own sinful purposes.

The New Testament gives us clear examples of demons—and even Satan himself—indwelling human beings and causing them to act in horrific ways. For instance, the Gadarene demoniac behaves in an uncontrollable manner with superhuman strength (Mark 5:1–20). Separating the actions of the man from the actions of the demons is, in such cases, nearly impossible. Judas also behaved in a manner that made him culpable for his sin, though John makes it clear that Satan had entered him (John 13:27).

Of course, I may be wrong, and the Sethite interpretation may be correct after all. I certainly grant that the ancient view seems strange to our modern ears. But since Peter and Jude both appear to have held it, it seems to me the best interpretation of Genesis 6:1–4. Regardless of which interpretation is correct, though, the main point is plain: humanity was falling deeper and deeper into sin and running farther and farther away from God.

Editors’ note: This article was originally published at The Gospel Coalition.