The work of adornment corresponds to that of variety; and as the Fourth Day answers to the adornment of the heavens with luminaries, so the Fifth to the adornment of the elements (water and air). And the Word of God was present as the formative power in the first institution of the active principle in nature, which gives to the seed its power of reproduction; and to the celestial bodies power in regard of things which putrify.
- text taken from Compendium of the Summa Theologica of Saint Thomas Aquinas, by Bishop Berardus Bongiovanni