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how did the ancient israelites' understanding of the cosmos differ from modern scientific models?

Adds the setting and its conversation across both testaments.

Genesis 1:6-8

“God said, “Let there be an expanse in the middle of the waters, and let it divide the waters from the waters.” God made the expanse, and divided the waters which were under the expanse from the waters which were above the expanse; and it was so. God called the expanse Sky. There was evening and there was morning, a second day.”

This passage is from the opening chapter of Genesis, part of the foundational texts of ancient Israel. It describes the second day of creation, where God establishes a division within a primordial body of water, forming the sky as a barrier.

What does it mean for us today to hold both ancient texts and modern scientific understanding, without reducing one to the other?

Then — the setting

This passage reflects a common ancient Near Eastern (ANE) cosmology, though with significant theological distinctives. The Israelites, like their neighbors, largely understood the cosmos as a three-tiered structure: a flat earth, often seen as floating on water, with a solid dome (the 'expanse' or 'firmament') above it separating earthly waters from heavenly waters. Above this dome were the 'waters above' and the dwelling of God. Below the earth was the realm of the dead (Sheol). This worldview was observational and analogical, describing reality as it appeared, rather than through abstract scientific principles or instrumental observation.

Across the Testaments

The Old Testament, particularly Genesis 1, presents a cosmology where God actively orders a pre-existing watery chaos. The New Testament does not offer a new cosmological model, but rather assumes the existing one while re-interpreting its theological significance. For instance, Paul in Romans 1:20 speaks of creation revealing God's attributes, echoing the Old Testament's view of creation as a testament to divine power and wisdom. However, the NT's focus shifts more to Christ's role in creation (e.g., Colossians 1:16, John 1:3) and the 'new creation' (e.g., 2 Corinthians 5:17), moving beyond a literal description of the physical structure of the cosmos to emphasize its theological meaning and Christological purpose.

Keep thinking

Read alongside it

Job 38:4-7
This passage presents God questioning Job about the foundations of the earth, highlighting divine wisdom in cosmic design.
Psalm 19:1
This psalm speaks of the heavens declaring God's glory, connecting the created order with divine revelation.
2 Peter 3:5-7
This New Testament passage references the creation by water and word, and points to a future destruction by fire, reflecting ongoing cosmic themes.

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