Gen 1:6-8
The Second Day. - When the light had been separated from the darkness, and day and night had been created, there followed upon a second fiat of the Creator, the division of the chaotic mass of waters through the formation of the firmament, which was placed as a wall of separation (מבדּיל) in the midst of the waters, and divided them into upper and lower waters. רקיע .s, from רקע to stretch, spread out, then beat or tread out, means expansum, the spreading out of the air, which surrounds the earth as an atmosphere. According to optical appearance, it is described as a carpet spread out above the earth (Psa 104:2), a curtain (Isa 40:22), a transparent work of sapphire (Exo 24:10), or a molten looking-glass (Job 37:18); but there is nothing in these poetical similes to warrant the idea that the heavens were regarded as a solid mass, a σιδήρεον, or χάλκεον or πολύχαλκον, such as Greek poets describe. The רקיע (rendered Veste by Luther, after the στερέωα of the lxx and firmamentum of the Vulgate) is called heaven in Gen 1:8, i.e., the vault of heaven, which stretches out above the earth. The waters under the firmament are the waters upon the globe itself; those above are not ethereal waters beyond the limits of the terrestrial atmosphere, but the waters which float in the atmosphere, and are separated by it from those upon the earth, the waters which accumulate in clouds, and then bursting these their bottles, pour down as rain upon the earth. For, according to the Old Testament representation, whenever it rains heavily, the doors or windows of heaven are opened (Gen 7:11-12; Psa 78:23, cf. 2Ki 7:2, 2Ki 7:19; Isa 24:18). It is in (or with) the upper waters that God layeth the beams of His chambers, from which He watereth the hills (Psa 104:13), and the clouds are His tabernacle (Job 36:29). If, therefore, according to this conception, looking from an earthly point of view, the mass of water which flows upon the earth in showers of rain is shut up in heaven (cf. Gen 8:2), it is evident that it must be regarded as above the vault which spans the earth, or, according to the words of Psa 148:4, “above the heavens.”