According To The Teaching of St. Thomas Aquinas
PART FIRST.
THE ORDINARY PRESENCE OF GOD IN ALL CREATURES ²
We may compare God's action with that of the sun. Although vastly distant from our planet, it still comes into contact with it through its rays, else how could it give light and heat to the earth? But God works in every created thing, not only through the medium of secondary causes as the sun acts upon the earth, but also in a direct and immediate way, by Himself bringing into existence and preserving in things that which is most intimate and deep-rooted in them, namely, their very being. For, as the characteristic effect of fire is to burn, so the characteristic effect of God, Who is Being itself, is to cause the being of creatures. "And so God is intimately present to all things as their efficient cause—as causing the being of all things." (Summa Theologica, I., q. viii., a. 1.)
God, then, is not present to the world like the artisan or the artist; he is external to his work, and does not often touch it in a direct way, but rather through his instruments, or is present to his work when he produces it, but later on withdraws from it without endangering its existence. God is so intimately united to the works of His hands that if, after calling a created thing into being, He should withdraw from it and cease to sustain it, it would immediately fall into the nothingness out of which it was made.
