not exist, the reason being that a square
circle involves a contradiction. And the reason, on the other hand, why
substance exists follows from its nature alone, which involves
existence. But the reason why a circle or triangle exists or does not
exist is not drawn from their nature, but from the order of corporeal
nature generally; for from that it must follow either that a triangle
necessarily exists, or that it is impossible for it to exist. But this
is self-evident. Therefore it follows that if there be no cause nor
reason which hinders a thing from existing, it exists necessarily. If
therefore there be no reason nor cause which hinders God from existing,
or which negates His existence, we must conclude absolutely that He
necessarily exists. But if there be such a reason or cause, it must be
either in the nature itself of God or must lie outside it, that is to
say, in another substance of another nature. For if the reason lay in a
substance of the same nature, the existence of God would be by this very
fact admitted. But substance possessing another nature could have
nothing in common with God, and therefore could not give Him existence
nor negate it. Since, therefore, the reason or cause which could negate
the divine existence cannot be outside the divine nature, it will
necessarily, supposing that the divine nature does not exist, be in His
nature itself, which would therefore involve a contradiction. But to
affirm this of the Being absolutely infinite and consummately perfect is
absurd. Therefore neither in God nor outside God is there any cause or
reason which can negate His existence, and therefore God necessarily
exists....

_The Corporeality of God_

There are those who imagine God to be like a man, composed of body and
soul and subject to passions; but it is clear enough from what has
already been demonstrated how far off men who believe this are from the
true knowledge of God. But these I dismiss, for all men who have in any
way looked into the divine nature deny that God is corporeal. That He
cannot be so they conclusively prove by showing that by "body" we
understand a certain quantity possessing length, breadth, and depth,
limited by some fixed form; and that to attribute these to God, a being
absolutely infinite, is the greatest absurdity. But yet at the same
time, from other arguments by which they endeavor to confirm their
proof, they clearly show that they remove altogether from the divine
nature