17. God placed them in the expanse of the heavens to give light on the earth,
18. and to govern the day and the night, and to separate the light from the darkness; and God saw that it was good.
19. There was evening and there was morning, a fourth day.
20. Then God said, "Let the waters teem with swarms of living creatures, and let birds fly above the earth in the open expanse of the heavens."