If we believe (as we must) that God is Pure Act, we are also compelled to acknowledge that He is perfect, the Supreme Good, Infinite in Power, Ubiquitous, Immutable and Eternal. The greater the simplicity of an immaterial thing, the greater, likewise, will be its perfection. God being absolutely devoid of complexity, Pure Act, and Simplicity Itself, we must also conclude that in Him is supreme Goodness and Perfection.

Again, as everything possesses greater power and virtue, in proportion as it is raised above matter, and becomes more formal; God, as Pure Act, being supremely elevated above all imperfection, and in the highest degree Formal, must be infinite, and infinitely Powerful. And, just as particular effects are reduced to particular causes, universal effects must be reduced to universal causes. Now, being is the most universal of all effects, because it is common to all things; it must therefore proceed from an Universal Cause, which is God, who is the Cause of being, not only by giving it, but also by preserving it. And, since it is necessary that when the cause operates, it must join its power to its effect, God, being His own Power, must be united to the being of all things. Therefore He must be intimately in all things, because being is more closely allied to nature than any other thing.

God, being indivisible, must be in the whole universe, and wholly in each of its parts. He is likewise immutable; because everything that changes must needs be composite, and God, being Pure Act, can know no change. He must necessarily also be eternal; because, were He not eternal, He would be mutable, having beginning and end; and thus He would not be God, but a being dependent on other things, and consequently not the First Cause.