Genesis 1:7
And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so.
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And divided the waters which were under the firmament from the waters which were above the firmament; the lower part of it, the atmosphere above, which are the clouds full of water, from whence rain descends upon the earth; and which divided between them and those that were left on the earth, and so under it, not yet gathered into one place; as it now does between the clouds of heaven and the waters of the sea. Though Mr. Gregory (a) is of opinion, that an abyss of waters above the most supreme orb is here meant; or a great deep between the heavens and the heaven of heavens, where, as in storehouses, the depth is laid up; and God has his treasures of snow, hail, and rain, and from whence he brought out the waters which drowned the world at the universal deluge. Others suppose the waters above to be the crystalline heaven, which for its clearness resembles water; and which Milton (b) calls the "crystalline ocean"...- John Gill
Genesis 1:8
And God called the firmament Heaven.
Genesis 1:14
And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:
Genesis 1:15
And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
Genesis 1:16
And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.
Genesis 1:17
And God set them in the firmament of the heaven to give light upon the earth,