_I answer that,_ It is absolutely true that God is not a body; and this
can be shown in three ways. First, because no body is in motion unless
it be put in motion, as is evident from induction. Now it has been
already proved (Q. 2, A. 3), that God is the First Mover, and is
Himself unmoved. Therefore it is clear that God is not a body.
Secondly, because the first being must of necessity be in act, and in
no way in potentiality. For although in any single thing that passes
from potentiality to actuality, the potentiality is prior in time to
the actuality; nevertheless, absolutely speaking, actuality is prior
to potentiality; for whatever is in potentiality can be reduced into
actuality only by some being in actuality. Now it has been already
proved that God is the First Being. It is therefore impossible that in
God there should be any potentiality. But every body is in
potentiality because the continuous, as such, is divisible to
infinity; it is therefore impossible that God should be a body.
Thirdly, because God is the most noble of beings. Now it is impossible
for a body to be the most noble of beings; for a body must be either
animate or inanimate; and an animate body is manifestly nobler than
any inanimate body. But an animate body is not animate precisely as
body; otherwise all bodies would be animate. Therefore its animation
depends upon some other thing, as our body depends for its animation
on the soul. Hence that by which a body becomes animated must be
nobler than the body. Therefore it is impossible that God should be a
body.

Reply Obj. 1: As we have said above (Q. 1, A. 9), Holy Writ
puts before us spiritual and divine things under the comparison of
corporeal things. Hence, when it attributes to God the three
dimensions under the comparison of corporeal quantity, it implies His
virtual quantity; thus, by depth, it signifies His power of knowing