Gen 1:6. And God said: let there be a firmament betwene the waters, and let it make a diuision betwene waters and waters. (Bishop’s Bible, 1568)
Gen 1:6. Againe God saide, Let there be a firmament in the middes of the waters: and let it separate the waters from the waters. (Geneva Bible, 1587)
Gen 1:6. And God said, Let there be a firmament in the midst of the waters: and let it diuide the waters from the waters. (KJV, 1611)
Gen 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. (RV, 1881)
Gen 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. (ASV, 1901)
Gen. 1:6 And God said, “Let there be a firmament in the midst of the waters, and let it separate the waters from the waters.” (RSV, 1952)
Merriam-Webster Online Dictionary:
Full Definition of FIRMAMENT
1
: the vault or arch of the sky :
heavens
2
obsolete :
basis
Which existed before the flood.
3
: the field or sphere of an interest or activity <the international fashion firmament>
Origin of FIRMAMENT
Middle English, from Late Latin & Latin; Late Latin firmamentum, from Latin, support, from firmare
Notice especially definition 1: the vault or arch of the sky. In Modern Hebrew, the word רָקִיעַ expresses the concept of the sky as viewed from the earth, especially at night.
6. And God said, “Let there be a dome in the midst of the waters, and let it separate the waters from the waters.”
7. So God made the dome and separated the waters that were under the dome from the waters that were above the dome. And it was so.
8. God called the dome Sky. And there was evening and there was morning, the second day. (NRSV)
6. Then God said, “Let there be a dome in the middle of the waters, to separate one body of water from the other.” And so it happened:
7. God made the dome, and it separated the water above the dome from the water below it.
8. God called the dome “the sky.” Evening came, and morning followed-the second day. (NAB)
The NRSV, the NAB, and many other English translations correctly translate the Hebrew word רָקִיעַ (râqı̂ya‛) as “dome.” The evidence for the correctness of this translation is found in the use of this word in ancient Hebrew literature. Based upon this usage, the Hebrew and English Lexicon of the Old Testament by Brown, Driver, and Briggs published by Oxford University gives us the following meaning of it in Gen. 1:6, 7, and 8, “the vault of heaven, or ‘firmament,’ regarded by Hebrews as solid, and supporting ‘waters’ above it.” (p. 956). John Skinner, Principal and Professor of Old Testament Language and Literature, Westminster College, Cambridge (in his commentary on Genesis, page 21) writes,
6-8 Second Work: The Firmament.—The second fiat calls into existence a
firmament, whose function is to divide the primeval waters into an upper and lower ocean, leaving a space between as the theater of further creative developments. The “firmament” is the dome of heaven, which to the ancients was no optical illusion, but a material structure, sometimes compared to an “upper chamber” (Ps. 104:12, Am 9:6) supported by “pillars” (Jb 26:11), and resembling in its surface a “molten mirror” (Jb 37:18). Above this are the heavenly waters, from which the rain descends through “windows” or “doors” (Gn 7:11,