The Firmament   The word 'firmament' comes from the Hebrew word רָקִיעַ meaning "expansion" or "expanse". The root verb form carries the idea "to stretch, spread out, expand", as indicated in a couple of the following verses [see also 'Stretcheth The Heavens'].  As Genesis explains, the firmament is that expanse between the waters above and the waters under.  King David, who lived over 1300 after the flood, said in Psalm 148:4, "Praise him, ye heavens of heavens, and ye waters that be above the heavens."
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.
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.
1:8 And God called the firmament Heaven. And the evening and the morning were the second day.
1:9 And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so.
1:10 And God called the dry land Earth; and the gathering together of the waters called he Seas: and God saw that it was good.
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:
1:15 And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
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.
1:17 And God set them in the firmament of the heaven to give light upon the earth,
1:18 And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.
1:19 And the evening and the morning were the fourth day.
1:20 And God said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven.
7:11 In the six hundredth year of Noah's life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened.
8:2 The fountains also of the deep and the windows of heaven were stopped, and the rain from heaven was restrained;
Job 37:18 Hast thou with him spread out the sky, which is strong, and as a molten looking glass?
Psalms
19:1 The heavens declare the glory of God; and the firmament sheweth his handywork.
104:1 Bless the LORD, O my soul. O LORD my God, thou art very great; thou art clothed with honour and majesty.
104:2 Who coverest thyself with light as with a garment: who stretchest out the heavens like a curtain:
104:3 Who layeth the beams of his chambers in the waters: who maketh the clouds his chariot: who walketh upon the wings of the wind:
Isaiah
34:4 And all the host of heaven shall be dissolved, and the heavens shall be rolled together as a scroll: and all their host shall fall down, as the leaf falleth off from the vine, and as a falling fig from the fig tree.
66:1 Thus saith the LORD, The heaven is my throne, and the earth is my footstool: where is the house that ye build unto me? and where is the place of my rest?
2 Peter 3:10 But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up.