Since God is a Perfect Cause with infinite power and infinite goodness, all His works must necessarily be of the Greatest Perfection. Now ORDER is one of the primary qualities of a being of infinite intelligence. Thus it must follow that the universe and all existing within the universe, both in its whole and in its tiniest most infinitesimal part, as also in its unity or its united operation - must have a most Perfect or STUPENDOUS ORDER.
Saint Thomas Aquinas as do all traditional Catholic scholars, tell us that God must constantly rule the world by His Divine Providence, else all would fall back into nothingness. By His creative act, God brought everything which now exists outside of Himself, into existence. But this requires His holding in existence everything which He created.
Further, we know that God created every being to seek its own perfection, in addition to contributing to the perfection of the whole of creation. Perhaps this latter quality of His STUPENDOUS ORDERING is the most difficult to comprehend by any mind except that MIND which sees all. In addition every functional part of every being is moved to its own good and the good of the whole being of which it is a part. And so the intellect of man naturally seeks truth, and the will naturally seeks the good. This must be necessary for man to seek his/her own perfection. And likewise the whole body and all its parts naturally seek their own good and the good of the whole body.
A first principle in this regard is: The lessor or lower being is for the higher, in a hierarchy of subjection and order. Thus for example God feeds grass eating animals with the grasses which He planted, and then feeds meat eating animals with the flesh of the grass-eaters.
*** LINK TO ORDERED UNIVERSE