The answer is: Heaven

Gen 1:8 - The NIV calls the firmament 'sky'.

The firmament, referred to as "Heaven" or "sky" in different translations, offers a fascinating glimpse into the ancient worldview of creation. In Genesis 1:8, this term underscores an understanding of the universe that encapsulated both the physical sky above and the broader spiritual realm. Imagine stepping outside thousands of years ago, gazing up at the sprawling expanse dotted with stars, and seeing that celestial blanket as a divine creation—an awe-inspiring architectural wonder by the Creator.

Fun fact: The Hebrew word "rakia," often translated as "firmament," gives the impression of something solid or beaten out—like a metal sheet stretched over below. It paints a rich picture of expansiveness but implies a form of separation, emphasizing that in connecting Heaven and Earth, God installed order in an otherwise chaotic void.

In addition to being a boundary, the firmament served practical purposes. It allowed rain and water vapor to cycle through—a heavenly plumbing system, so to speak! Creatures of the air and planets above reflect themes of dominion ingrained in creation, where harmony unfolds as part of God’s original plan.

Symbolically, the firmament invites contemplation on the enclosed nature of humanity's relationship with the divine. Just as the firmament separates waters and welcomes the sun, a clear sky enables the light of truth and reason to shine through. In questioning, discovering, and eco-connecting more deeply, we mimic that exquisite cosmic dance initiated at the dawn of time.