Pirkei DeRabbi Eliezer, a fascinating early medieval text, gives us a deeper dive.

On the second day, this text tells us, the Holy One, blessed be He, didn't just create the firmament. It also brought into being the angels, the fire destined for humanity, and even the fire of Gehinnom (גהנום), often translated as Hell. Quite a busy day!

Now, hold on, you might be thinking. Didn't Genesis 1:1 clearly state, "In the beginning God created the heaven and the earth"? So, what's this firmament creation all about? Rabbi Eliezer cuts through the apparent contradiction. The firmament created on the second day, he explains, is a very specific one: the firmament above the heads of the four Chajjôth (חיות), the living creatures described in Ezekiel's vision.

Ezekiel 1:22 gives us a glimpse: "And over the head of the Chajjôth there was the likeness of a firmament, like the colour of the terrible crystal." What does that even mean? According to Rabbi Eliezer, this "terrible crystal" shimmers like precious stones and pearls, radiating light throughout the heavens. Imagine a lamp illuminating an entire house, or the sun blazing at its midday peak.

It's a light so powerful, so pure, that Daniel 2:22 says, "The light dwelleth with him." And it's a light that awaits the righteous in the world to come. As Daniel 12:3 promises, "And they that be wise shall shine as the brightness of the firmament."

But this firmament isn't just about dazzling light. It serves a crucial cosmic function. Without it, the text asserts, the world would be overwhelmed by the waters above and the waters below. Remember Genesis 1:6? "And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters." This firmament acts as a divider, a separator, creating a space, a haven, between the upper and lower waters.

So, the second day of Creation wasn't just about physical separation. It was about establishing order, creating a boundary, and unleashing a light that both sustains the world and illuminates the path for those who strive for righteousness. It’s a reminder that even amidst the chaos of creation, there is structure, purpose, and a promise of radiant light to come.