Keil and Delitzsch on Genesis 6: Sons of God as Godly Men

Carl Friedrich Keil and Franz Delitzsch were 19th‑century conservative Lutheran Old Testament scholars whose multi‑volume Commentary on the Old Testament has shaped generations of interpreters. In their exposition of Genesis 6:1–4, they argue that the “sons of God” are pious human beings from the godly line, especially Seth’s descendants, and that the “daughters of men” are the rest of mankind, particularly the Cainite line. The Nephilim, for them, are violent human tyrants already present before these mixed marriages, not angel‑human hybrids. They therefore firmly reject both the angelic‑marriage view and the idea that the “sons of God” are royal or aristocratic rulers.

Keil and Delitzsch’s Sethite Reading of Genesis 6

Keil and Delitzsch treat Genesis 6:1–4 as part of the continuous story running from Genesis 4 through the flood. Genesis has already distinguished two moral trajectories: the line of Cain, marked by violence and cultural brilliance divorced from God, and the line of Seth, in which people “began to call upon the name of the Lord” and figures like Enoch and Noah “walked with God.” Against that backdrop, they identify the “sons of God” in Genesis 6:2 as godly men from this pious line, and the “daughters of men” as women drawn from the rest of humanity, especially the Cainite world.

They insist that the key question—are these “sons of Elohim” heavenly beings or human believers—cannot be settled merely by word studies. As they put it, “The question whether the ‘sons of Elohim’ were celestial or terrestrial sons of God (angels or pious men of the family of Seth) can only be determined from the context, and from the substance of the passage itself, that is to say, from what is related respecting the conduct of the sons of God and its results” (Commentary on the OT, Genesis 6:1–4, section on the three views). In their method, the narrative setting and consequences of the marriages carry decisive weight.

Very early in their discussion, they lay out three main options: (1) the “sons of God” are royal or aristocratic rulers, (2) they are angels who take human wives, or (3) they are pious human beings, particularly from Seth’s family. They adopt the third, while treating the ruler view as linguistically baseless and the angelic view as both theologically and contextually impossible.

On their reading, Genesis 6 describes a collapse of the moral separation between those walking with God and the rest of the human race. Godly men began to choose wives simply on the basis of outward beauty, “any they chose,” without regard for spiritual allegiance. That intermarriage broke down the last barriers against universal corruption, so that “every intention of the thoughts” of human hearts became only evil continually (Genesis 6:5). God’s pronouncement in Genesis 6:3, limiting the period before the flood to 120 years, is thus directed entirely at humanity, as is the judgment that follows.

They also clarify that “daughters of men” does not, for them, denote a special social class; it is the rest of mankind, defined by contrast with the “sons of God.” Likewise, they define “Nephilim” as violent invaders or oppressors already present in those days, distinct from the children born to the mixed marriages. This severs any link between the Nephilim and putative angel‑human hybrids. Finally, they argue that New Testament texts about sinning angels—2 Peter 2:4 and Jude 6–7—must be read on their own terms and, in their judgment, speak of angelic rebellion and confinement but not of angels marrying women or fathering the Nephilim.

The following table sets out the three main Genesis 6 options they consider and how they evaluate each.

Who Are the ‘Sons of God’ and ‘Daughters of Men’?

Keil and Delitzsch begin their positive exegesis by asking how the Old Testament itself uses the phrase “sons of God.” They acknowledge that in books like Job it can denote heavenly beings, but they then survey passages where related language describes the people of God. From this they argue that one cannot decide the question by Hebrew lexicons alone: “These passages show that the expression ‘sons of God’ cannot be elucidated by philological means, but must be interpreted by theology alone.” (Genesis 6:1–2, discussion of Old Testament usage).

The theological move they make is that if “sons of God” were a physical term, naming beings begotten out of God’s own essence, it would fit neither angels nor humans. Once that physical idea is set aside, the title can be applied to any creature that bears God’s image or shares in His life by likeness and fellowship. They argue, “But if the title ‘sons of God’ cannot involve the notion of physical generation, it cannot be restricted to celestial spirits, but is applicable to all beings which bear the image of God, or by virtue of their likeness to God participate in the glory, power, and blessedness of the divine life,—to men therefore as well as angels.” (Genesis 6:1–2, theological explanation of the phrase).

They then look back into the pre‑flood narrative. Genesis has already spoken of people who “walked with God,” such as Enoch and Noah. It has depicted a line in which calling on the name of the Lord is a defining mark. For Keil and Delitzsch, this is precisely what one would expect if there were “sons of God” on the earth long before Israel existed. They write, “If in the olden time there were pious men who, like Enoch and Noah, walked with Elohim, or who, even if they did not stand in this close priestly relation to God, made the divine image a reality through their piety and fear of God, then there were sons (children) of God, for whom the only correct appellation was ‘sons of Elohim.’” (Genesis 6:1–2, argument from pre‑Israelite piety).

On that basis, they conclude that in Genesis 6:2 “sons of God” designates godly men, especially from the Sethite line, who had been marked by devotion to the Lord. The “daughters of men,” by contrast, are women from the wider, ungodly humanity. They answer a common objection: since “man” (hāʾādām) means the whole human race in Genesis 6:1, must not “daughters of men” in verse 2 also mean all women without distinction? Keil denies that the inference is necessary: “It by no means follows, that because in Genesis 6:1 הָאָדָם denotes man as a genus, i.e., the whole human race, it must do the same in Genesis 6:2, where the expression ‘daughters of men’ is determined by the antithesis ‘sons of God.’” (Genesis 6:1–2, answer to the antithesis argument).

Within the broad category “man,” Scripture can thus distinguish two subsets: those who live as God’s children in faith, and those who do not. “Daughters of men,” framed by its opposite, names the latter group. For Keil and Delitzsch, Genesis 6 does not suddenly introduce angels into the story; it describes what happens when the line that had remained faithful abandons God’s standards in marriage.

The phrase “they took them wives” (Genesis 6:2) is crucial. Keil stresses that this is not language of rape or casual immorality but of formal marriage: “Now אִשָּׁה לָקַח (to take a wife) is a standing expression throughout the whole of the Old Testament for the marriage relation established by God at the creation, and is never applied to porneia, or the simple act of physical connection. This is quite sufficient of itself to exclude any reference to angels.” (Genesis 6:2, discussion of “they took them wives”). The sin lies not in marriage as such but in choosing spouses solely on the ground of physical attractiveness and desire, disregarding the spiritual divide that Genesis has drawn between the Sethite and Cainite ways of life.

On their reading, this intermarriage erases the last visible distinction between a God‑fearing community and the broader culture. As the children of such unions grow up, the distinct piety of the “sons of God” line fades. Within a few generations, violence and corruption dominate the earth. The marriages of Genesis 6:1–2 are therefore not an odd side‑episode but the mechanism by which the godly line itself is absorbed into a humanity that has already turned from God, leaving only Noah as a righteous remnant.

Why They Reject Angelic Marriages in Genesis 6

Keil and Delitzsch consider two non‑Sethite options and reject both. The first is the old rabbinic idea that the “sons of God” are royal or aristocratic men who take commoners as wives. After outlining it, they write: “Of these three views, the first, although it has become the traditional one in orthodox rabbinical Judaism, may be dismissed at once as not warranted by the usages of the language, and as altogether unscriptural.” (Genesis 6:1–2, early paragraph on three views). In their judgment, nothing in the Hebrew phrase “sons of God” suggests social rank or royal status, and there is no hint in the context of a critique of aristocratic polygamy as such.

The lion’s share of their polemic is directed at the angelic‑marriage view. Several of their main objections are as follows.

Old Testament marriage idiom and the nature of angels. As noted, they take the idiom “to take a wife” as decisive evidence that Genesis 6 describes ordinary human marriages. For them, it is inappropriate to read that fixed phrase as pointing to an unprecedented union between angels and humans. This linguistic argument is joined to a theological one: angels, as Scripture presents them, are created spirits who do not reproduce. They argue that to construe “sons of God” here in a physical, generative sense either implies that angels are begotten out of the divine essence or that they acquire reproductive powers never given them in creation—both of which they regard as unscriptural and akin to gnostic speculation (Genesis 6:1–4, theological discussion of angelic nature).

They also appeal to Christ’s statement that angels in heaven neither marry nor are given in marriage. In their reading, the marriage covenant belongs to human life; angelic fallenness may corrupt and darken a nature, but it does not add new natural faculties such as sexuality or procreative capacity.

The focus of the Genesis judgment. Another key point is the direction of judgment in Genesis 6–9. The narrative repeatedly emphasizes human wickedness and God’s response to it. After describing how great man’s wickedness had become, Moses writes that the Lord was grieved and determined to blot out “man” from the earth. Keil comments, “Now when the wickedness of man became great, and ‘every imagination of the thoughts of his heart was only evil the whole day,’ i.e., continually and altogether evil, it repented God that He had made man, and He determined to destroy them. This determination and the motive assigned are also irreconcilable with the angel-theory.” (Genesis 6:5–7, link between human wickedness and the flood).

On their reasoning, if angels were the principal corrupters by crossing a species boundary, it would be strange for the text to speak only of judgment on men and to pass over the angelic offenders in silence. Scripture elsewhere, such as in Genesis 3, records the punishment of the tempter alongside that of the tempted. That Genesis 6 mentions only human judgment suggests, for Keil and Delitzsch, that the story’s horizon is entirely within the human race.

Narrative context. They also stress that up to Genesis 6 the storyline has not introduced angels into the human genealogies and moral development it traces. By contrast, it has carefully followed the spread of sin and the persistence of worship through Cain’s and Seth’s lines. To import angels into Genesis 6 is therefore, in their view, to disrupt the narrative flow with beings who have not previously figured in this section of the story. Seeing “sons of God” as pious men, by contrast, keeps the focus on the question Genesis has been tracking from Cain and Abel onward: how sin spreads within humanity and how a godly line can be preserved.

Nephilim, Mighty Men, and New Testament ‘Sinning Angels’

Keil and Delitzsch read Genesis 6:3–4 and the related New Testament passages in a way that consistently reinforces their human‑only reading of the episode.

The 120 years in Genesis 6:3. When God says, “My Spirit shall not abide in man forever, for he is flesh: his days shall be 120 years,” they understand this not as a new cap on individual human lifespan but as a period of divine forbearance before the flood. God announces that humanity, having shown itself governed by fleshly desire rather than God’s Spirit, will receive 120 more years before judgment falls. In their commentary, this reinforces the theme that the crisis is moral and human, not biological or hybrid (Genesis 6:3, explanation of the 120 years).

The Nephilim and “mighty men.” In verse 4, the text says, “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.” Many interpreters link the Nephilim directly to the offspring of the mixed unions. Keil and Delitzsch argue instead that the wording distinguishes the Nephilim from those later “mighty men.” They state that “To an unprejudiced mind, the words, as they stand, represent the Nephilim, who were on the earth in those days, as existing before the sons of God began to marry the daughters of men, and clearly distinguish them from the fruits of these marriages.” (Genesis 6:4, explanation of the Nephilim).

On their etymology, “Nephilim” comes from a root meaning “to fall upon,” so that they are “invaders” or “tyrants” rather than necessarily “giants.” They view the common giant interpretation as a later, Septuagint‑influenced embellishment. The “mighty men of renown,” by contrast, are the children born to the mixed marriages: notable figures in their own right, famed for power or exploits, but not identical with the Nephilim. In any case, all these groups are, in their reading, fully human. The text nowhere says that these heroes differ in nature from other men; their notoriety lies in their deeds, not in monstrous physiology.

2 Peter 2:4 and Jude 6–7. Keil and Delitzsch affirm that some angels sinned, were cast down, and are kept for judgment; they acknowledge the plain teaching of 2 Peter 2:4 and Jude 6. What they deny is that these texts tell us anything about angels marrying women. “Nor do 2 Peter 2:4 and Jude 1:6 furnish any evidence of angel marriages. Peter is merely speaking of sinning angels in general (angelōn hamartēsantōn) whom God did not spare, and not of any particular sin on the part of a small number of angels.” (extended note attached to Genesis 6:1–4, section critiquing New Testament appeal to angel marriages).

On Jude 6–7, they offer a more detailed grammatical and theological case. Jude says that certain angels “did not stay within their own position of authority, but left their proper dwelling,” and that Sodom and Gomorrah, “in like manner to these,” indulged in sexual immorality and pursued “strange flesh.” Many angel‑view advocates take “in like manner to these” to link angelic and human sexual sin and see “strange flesh” as pointing back to angel‑human unions. Keil and Delitzsch respond that the Greek pronoun can naturally refer to the cities just mentioned or to Jude’s ungodly opponents, and that “strange flesh” presupposes that the parties in question have flesh of their own. Since angels, as they understand Scripture, are incorporeal spirits, applying “strange flesh” to them either requires one to ascribe flesh to angels or empties the phrase of sense. They therefore conclude, “In this description of the angels’ sin, there is not the slightest allusion to their leaving heaven to woo the beautiful daughters of men.” (note on Jude 6–7, within the Genesis 6 discussion).

They also address the appeal to 1 Enoch and related Second Temple legends about angelic Watchers. In their view, such writings may reveal what some Jews believed but do not carry doctrinal authority or control the exegesis of Genesis or the New Testament. Peter and Jude, they argue, omit the distinctive Enochic details (such as the descent of 200 angels to take wives, iron chains, and specified generations) and instead define the angels’ sin as abandoning their assigned position and habitation. For Keil and Delitzsch, this omission is deliberate and indicates that the apostles “gave no credence” to the marriage legends (Genesis 6:1–4, excursus on 1 Enoch and apostolic silence).

The following table gathers how they coordinate specific motifs in Genesis 6 and the New Testament.

Theological Emphases and Limits of Their Discussion

Beyond the lexical and contextual decisions, Keil and Delitzsch highlight several theological themes. One is the nature of divine “repentance” in Genesis 6:6. They argue that readers should not infer a changeable or ignorant deity from the language that God “repented” of making man. Instead, they gloss it as a vivid figure for God’s holy grief: “The repentance of God is an anthropomorphic expression for the pain of the divine love at the sin of man, and signifies that ‘God is hurt no less by the atrocious sins of men than if they pierced His heart with mortal anguish’ (Calvin).” (Genesis 6:6, explanation of divine repentance).

Another emphasis is that Scripture itself grounds the necessity of the flood in human wickedness, not in the emergence of a hybrid race. They point out that Genesis 8:21, after the flood, still affirms that “the intention of man’s heart is evil from his youth,” and yet God now pledges not to destroy all living creatures again in this way. For Keil and Delitzsch, this shows that one cannot deduce the logic of the flood simply from speculative calculations about how corrupt the world must have become; the interpreter should stay with the text’s own explanation that God judged “the men whom He had created” when their wickedness became universal (Genesis 6:5–7 and 8:21, theological reflection on the rationale of the flood).

They are also restrained about details the text does not specify. Genesis 6 shows intermarriage between godly and ungodly, rising tyranny, and pervasive violence, but the precise political structures or cultural mechanisms remain unexplained. Keil and Delitzsch note these features without attempting to reconstruct a full sociology of pre‑flood civilization. Likewise, while they accept that some angels fell and are kept for judgment, they decline to speculate about how or exactly when that rebellion unfolded beyond what Peter and Jude state. Non‑canonical works like 1 Enoch may illustrate later Jewish imagination but, in their view, do not determine biblical exegesis.

Conclusion

In Keil and Delitzsch’s reading of Genesis 6, the “sons of God” are godly humans, particularly from Seth’s line; the “daughters of men” are the rest of humanity, especially the Cainite world. Their intermarriage erases the separation between the godly and the ungodly, accelerates moral collapse, and leads directly into the flood, which is God’s judgment on the universal wickedness of the Adamic race. The Nephilim are not angel‑human hybrids but human tyrants already on the scene, and the “mighty men of renown” who arise from the mixed marriages are likewise fully human. New Testament references to sinning angels reaffirm that some angels rebelled and are kept for judgment, but, on their reading, do not speak of angelic marriages or confirm an angelic interpretation of Genesis 6.

As conservative Lutheran Old Testament commentators writing in the 19th century, Keil and Delitzsch combine close attention to Hebrew philology with a theological reading that situates Genesis 6 within the flow of Genesis 4–9 and within broader biblical teaching on creation, angels, sin, and judgment.

Key takeaways from their treatment include:

“Sons of God” in Genesis 6:2 are best read, in their view, as pious human beings rather than angels or rulers; the phrase must be interpreted theologically and contextually, not by philology alone. The narrative’s focus on human marriage language, universal human wickedness, and human‑directed judgment rules out angelic unions. The Nephilim and later “mighty men” remain fully human figures of violence and fame, distinguished from one another in the text. New Testament “sinning angel” passages speak of angelic rebellion and confinement but, on their analysis, offer “not the slightest allusion” to marriages with women.

This article has summarized their argument as presented in the Genesis 6 section of their Commentary on the Old Testament, with citations to specific paragraphs in that exposition and in the related notes on 2 Peter 2 and Jude 6–7. Their conclusions rest on a combination of lexical observation, narrative context, and comparison with other biblical passages.

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