The need for space is a fundamental necessity.
Immediately after bringing in light, the Creator introduced expanse.
The Hebrew reading indicates the graphic installation of the sky in between the waters below and the waters above. The only way to visualize the Day 2 creation account is to have the text tell us how it really was.
Water, Space, Water.
For the scripturally adept, we know where the former water eventually went. It poured down to earth in the great deluge, cradling Noah's ark.
What is of note however is the vault that was crafted in between the two waters.
The world I live in is overcrowded.
Without space, I will surely drown without help.
The sky reminds me of God's intentional grant of shalom amidst all present deluge.