“And God called the firmament Heaven. And the evening and the morning were the second day” (Genesis 1:8 ). So when God created “the heavens and the earth” (cf. Gen 1:1) the author did not mean the “firmament” that here is called also “heaven”. Is it perhaps a repetition?
I’ve already said that the expression “heaven and earth” in the very first verse of the Bible (Gen 1:1) is a typically Hebrew way of saying to express that God created “all that exists”. In the Creed, recited in churches every Sunday, is said that God is the creator of “all that is, seen and unseen“. So the “firmament” (Gen 1:8) – in Hebr. raqia – could be the seen and the “sky” (Gen 1:1) – in Hebr. shamaim – could be the “unseen”.
In the Bible the sky is the residence of God (see Psalm 32:10), but it is also the blue vault that we now call “firmament”, although today this term is used for the night sky. The “sky” is a symbol, a “visible thing” well known by astronomers, but it also makes you think of something that you don’t see and that cannot be defined by words or concepts: GOD .
Returning then to the eighth verse we could say that the “sky” of which we have been dealing with is the “Heaven” translated – perhaps improperly for English speaking readers – as “firmament”. What is then the “sky” of the first verse? It cannot be translated as God, for God couldn’t create a copy of Himself! We might think instead of the “invisible world” to which God himself belongs. Is it a real world or a symbolic one? It is the sky that science will never be able to define, but just as real for those who have faith, that is to say “the substance of things hoped for, the evidence of things not seen“. (Hebrews 11:1)
To explore further you can read my book: L’inganno del cherubino guardiano, 2014 .