[29] In the first place therefore, from the model of the world, perceptible only by intellect, the Creator made an incorporeal heaven, and an invisible earth, and the form of air and of empty space: the former of which he called darkness, because the air is black by nature; and the other he called the abyss, for empty space is very deep and yawning with immense width. Then he created the incorporeal substance of water and of air, and above all he spread light, being the seventh thing made; and this again was incorporeal, and a model of the sun, perceptible only to intellect, and of all the light-giving stars, which are destined to stand together in heaven.