This article is the fifth in a seven-part series exploring the Genesis 1 creation account. Examining the text through a historical-critical lens, this series unpacks the original Hebrew, the impact of ancient translations, and the profound theological meaning of each day of creation.

The literary elegance of Genesis 1 is most visible in its symmetrical architecture. The first three days of creation (forming) align perfectly with the next three days (filling). Day Four populated the domain of Time (Day One) with the sun, moon, and stars. Now, on Day Five, the text moves to populate the domains built on Day Two: the sky-vault (raqia) and the waters below it.
With the cosmos fully structured and a reliable system for tracking time established, the environment is finally ready to sustain biological life. Yet, as the author introduces the first living creatures into the narrative, they pause to deliver another sharp theological critique of the surrounding ancient world.

The Hebrew Text: Populating Sky and Sea

The text for the fifth day reads: “And God said, ‘Let the waters swarm with swarms of living creatures, and let birds fly above the earth across the vault of the sky.'” Following the command, the text gives a specific inventory of what God created: the great sea monsters, every living and moving thing that swarms in the water, and every winged bird. Until this moment, the only organic life created was vegetation on Day Three. Vegetation was bound to the earth and commanded to grow from the earth. On Day Five, we see the introduction of nephesh chayyah—breathing, animate, sentient creatures capable of autonomous movement.

The Polemic of the Tanninim

Verse 21 deliberately highlights a very specific creature: “So God created the great sea monsters (tanninim ha-gedolim)…” Why did the biblical author single out these specific animals?
To an ancient Near Eastern reader, the word tanninim was loaded with mythological baggage. In Ugaritic, Canaanite, and Babylonian mythology, the “Tannin” (often translated as dragons, sea serpents, or Leviathan) were terrifying, primordial monsters of chaos. They were often depicted as rival gods who rebelled against the chief creator deity and had to be violently subdued to maintain order in the universe.
The Priestly author of Genesis uses the word tanninim to completely demythologize them. By explicitly stating that God created the great sea monsters, the author strips them of their divine, rival status. In the worldview of Genesis, there are no chaotic monsters threatening the cosmic order. The sea dragons are not gods; they are simply large aquatic animals that YHWH sculpted, placed in the ocean, and looked upon with approval.

The First Blessing: The Goodness of Reproduction

Day Five is also highly significant because it contains the very first divine blessing in the biblical text: “God blessed them, saying, ‘Be fruitful and multiply and fill the waters in the seas, and let birds multiply on the earth.'”
In many later Hellenistic philosophies (and certain ascetic movements within later Christianity), the physical world, the biological body, and the act of reproduction were often viewed with suspicion or disdain—seen as a lower, messier existence compared to the pure realm of the spirit.
The Genesis narrative explicitly rejects this dualism. By issuing a formal blessing over biological reproduction, the author establishes that the physical body, the mating of animals, and the swarming, multiplying abundance of life are not necessary evils; they are inherently good, divine intentions for the created order. The world was not built to be an empty, static museum; it was designed to be a flourishing, teeming ecosystem.

This concludes Part 5 of our series. God has filled the sky and the seas, and blessed the animal kingdom. In Part 6, the symmetry of the creation week will reach its climax on Day Six, as the dry land is populated and the “Image of God” is finally placed within the cosmic temple.