God himself created the visible world in all its richness, diversity and order. Scripture presents the work of the Creator symbolically as a succession of six days of divine “work”, concluded by the “rest” of the seventh day. On the subject of creation, the sacred text teaches the truths revealed by God for our salvation, permitting us to “recognize the inner nature, the value and the ordering of the whole of creation to the praise of God.”
Nothing exists that does not owe its existence to God the Creator. the world began when God’s word drew it out of nothingness; all existent beings, all of nature, and all human history are rooted in this primordial event, the very genesis by which the world was constituted and time begun.
Each creature possesses its own particular goodness and perfection. For each one of the works of the “six days” it is said: “and God saw that it was good.” “By the very nature of creation, material being is endowed with its own stability, truth and excellence, its own order and laws.” Each of the various creatures, willed in its own being, reflects in its own way a ray of God’s infinite wisdom and goodness. Man must therefore respect the particular goodness of every creature, to avoid any disordered use of things which would be in contempt of the Creator and would bring disastrous consequences for human beings and their environment.
God wills the interdependence of creatures. the sun and the moon, the cedar and the little flower, the eagle and the sparrow: the spectacle of their countless diversities and inequalities tells us that no creature is self-sufficient. Creatures exist only in dependence on each other, to complete each other, in the service of each other.
The beauty of the universe: the order and harmony of the created world results from the diversity of beings and from the relationships which exist among them. Man discovers them progressively as the laws of nature. They call forth the admiration of scholars. the beauty of creation reflects the infinite beauty of the Creator and ought to inspire the respect and submission of man’s intellect and will.
The hierarchy of creatures is expressed by the order of the “six days”, from the less perfect to the more perfect. God loves all his creatures and takes care of each one, even the sparrow. Nevertheless, Jesus said: “You are of more value than many sparrows”, or again: “of how much more value is a man than a sheep!”
From the Catechism of the Catholic Church 337-342