“God said: Let there be a firmament in the midst of the waters” (Genesis 1:5 ). This is the first part of the fifth verse of the Hebrew Bible. The Hebrew Bible is also called Massoretic Text because it has been handed down and vocalized by the school of the “Masoretes”, active between the seventh and tenth centuries A.D.,
Here God is elohim. However it should not be translated as “gods”, because the subject, “he said ,” is in the singular. And even if there is someone that translates elohim as god, who wrote this chapter clearly intended elohim as singular name. Perhaps the author meant that his God was the Lord of all other deities worshiped at that time, ie at the end of the sixth century B.C.
In Hebrew, “firmament” is raqìa that means “solid barrier, rigid vault”. The latin translation “firmamentum” is very precise, because the term means “barrier separating the waters”. I’ll comment this latter phrase in a dedicated post. Here I simply say that for ancients hebrews, the sky was certainly not the “air”. It was instead a “dome”, a “vault” where were mounted the stars (see Revelation 12:4 ) and the other planets.
According to the way of thinking of the Ancient Hebrews, the earth was completely submerged by the primordial waters. The light shone upon the waters, while the darkness had been enclosed. There wasn’t still the sky, ie the blue vault above the earth: the firmament will fulfil this function. (To learn more on the subject you can read my book: L’inganno del cherubino guardiano)