Genesis 1:6

The firmament] the sky, heavens. The word means something 'solid' or 'beaten out,' like a sheet of metal. The ancients supposed that the sky was a solid, vaulted dome stretched over the earth, its ends resting on the mountains, and the heavenly bodies fastened to its inner surface. It served as the throne of God, cp. Exodus 24:10; Ezekiel 1:26. Its purpose here was to divide in two the primeval mass of waters. Above, it supported the upper waters which fell upon the earth through 'the windows of heaven (Genesis 7:11) in the form of rain; below were the waters on which the earth rested, and from which it emerged. These waters were supposed to form a subterranean abyss which supplied the springs and seas; for the idea cp. Genesis 7:11; Genesis 49:25; Deuteronomy 33:13; Job 38:16; Psalms 24:2; Proverbs 8:28, also Exodus 24:10; Ezekiel 1:26; This thought of the division of the primeval ocean into an upper and lower portion is represented in the Babylonian story by the cleaving of the body of Tiamat.

9-13. Third day:—Separation of land and wator. Creation of vegetation.

Let the dry land appear] by emerging from the flower waters which were now gathered into seas. See Psalms 104:6.

11, 12. Grass.. herb yielding seed.. tree yielding fruit] a dimple and popular classification of the vegetable? world. Whose seed is in itself] RV 'wherein' (i.e. in the fruit) 'is the seed thereof.' After his kind] i.e. according to their several species.

14-19. Fourth day:—Creation of sun, moon, and stars.

The special value of this part of the story lies in its opposition to the worship of the heavenly bodies as deities, which was such a prominent feature of heathenism in Babylonia and elsewhere. Here they are declared to be created for the service of man, fulfilling a definite purpose. That purpose was threefold: (a) 'to divide the day from the night'; (b) to be 'for signs, and for seasons, and for days, and years,' i.e. to give the means of reckoning time; (c) 'to give light upon the earth.'