Why does the LXX call the Nephilim 'giants'?

The Greek translators made a choice, and that choice shaped three thousand years of interpretation.

When the Jewish scholars in Alexandria translated the Hebrew Bible into Greek — producing what we call the Septuagint, or LXX, beginning in the third century BC — they reached Genesis 6:4 and found two Hebrew words that needed a Greek equivalent. The first was nephilim (H5303), the rare class-noun that the Hebrew text does not define. The second, in the same verse, was gibborim (H1368), the ordinary word for "mighty man" or "warrior."

They rendered both with the same Greek word: γίγαντες — gigantes, giants.

Here is how the verse reads in the LXX:

Οἱ δὲ γίγαντες ἦσαν ἐπὶ τῆς γῆς ἐν ταῖς ἡμέραις ἐκείναις ... ἐκεῖνοι ἦσαν οἱ γίγαντες οἱ ἀπ' αἰῶνος, οἱ ἄνθρωποι οἱ ὀνομαστοί.

"The gigantes were on the earth in those days ... those were the gigantes who are from the age, the men, the named ones." — LXX Gen 6:4

Two Hebrew terms, one Greek word, used twice in the same verse. LXX Numbers 13:33 does the same — the spies report seeing gigantes in Canaan.

Why does this matter?

Gigantes is not a neutral Greek word. In Hesiod's Theogony (written around 700 BC), the gigantes are the offspring of Heaven (Ouranos) and Earth (Gaia) — beings born from the union of a heavenly father and an earthly mother, who rebelled against the Olympian gods and were imprisoned beneath the earth after their defeat (Hesiod, Theogony 184-186; 617-735). The Greek-speaking world knew this story. Everyone who read the LXX and encountered γίγαντες immediately heard it.

The LXX translators were not importing mythology carelessly. They were choosing the closest available Greek word for beings described as born of a heavenly father (bene ha-elohim) and human mothers, who were larger and more powerful than ordinary humans. The word fit the referent. But the word came loaded with a whole mythological framework: heavenly-earthly parentage, extraordinary power, rebellion, imprisonment.

The consequence: an entire reading tradition

Once nephilim and gibborim are both γίγαντες in the standard Greek Bible, the angelic-descent reading of Genesis 6 is essentially the only reading available in Greek. There is no neutral way to read γίγαντες in the third century BC. The Hellenistic Jewish audience — and then the Greek-speaking church — received Genesis 6:4 through that word, and through the framework it carried.

This is precisely the bridge the Second Temple expansion traveled. The Book of the Watchers in 1 Enoch (written largely in the third to second century BC) expands Genesis 6 into a full narrative of two hundred heavenly beings descending to Mount Hermon, swearing a mutual oath, taking wives, fathering giants of tremendous size — and then being imprisoned when the archangels appeal to God. The LXX had already named the offspring of this union γίγαντες. 1 Enoch simply filled in the details.

The New Testament picks it up

By the time 2 Peter and Jude are written, the whole framework is in the air. Second Peter 2:4 uses the verb tartaroō (G5020) — "cast into Tartarus" — which is the technical term for where the gigantes of Hesiod were imprisoned. The LXX had called the offspring of Genesis 6 gigantes; Peter uses the mythological-origin vocabulary for where those beings are now held. The chain runs: Hebrew nephilim → LXX gigantes → Hellenistic framework of imprisoned heaven-and-earth offspring → 2 Peter's Tartarus.

What the LXX translation does not settle

The LXX's word choice tells us how Greek-speaking Jews read Genesis 6:4 — it does not tell us whether the translation is right. Gigantes loads the verse with Greek mythology that the Hebrew does not contain. The Hebrew nephilim is a class-noun that the text never glosses; the Hebrew gibborim describes martial power, not size. The LXX conflated two distinct Hebrew terms and introduced a mythological frame that the Hebrew held at arm's length.

But the translation happened, and it mattered enormously. Understanding why nephilim became giants — and what that choice unlocked in Jewish and Christian reception — is essential for reading the NT's own engagement with Genesis 6.

The full study examines the LXX translation table side by side with the MT in The Nephilim: What Genesis 6:1-4 Actually Says.