3: Further, to proceed from another seems to be against the
nature of the first principle. But God is the first principle, as
shown above (Q. 2, A. 3). Therefore in God there is no procession.

_On the contrary,_ Our Lord says, "From God I proceeded" (John 8:42).

_I answer that,_ Divine Scripture uses, in relation to God, names which
signify procession. This procession has been differently understood.
Some have understood it in the sense of an effect, proceeding from its
cause; so Arius took it, saying that the Son proceeds from the Father
as His primary creature, and that the Holy Ghost proceeds from the
Father and the Son as the creature of both. In this sense neither the
Son nor the Holy Ghost would be true God: and this is contrary to what
is said of the Son, "That . . . we may be in His true Son. This is
true God" (1 John 5:20). Of the Holy Ghost it is also said, "Know you
not that your members are the temple of the Holy Ghost?" (1 Cor.
6:19). Now, to have a temple is God's prerogative. Others take this
procession to mean the cause proceeding to the effect, as moving it,
or impressing its own likeness on it; in which sense it was understood
by Sabellius, who said that God the Father is called Son in assuming
flesh from the Virgin, and that the Father also is called Holy Ghost
in sanctifying the rational creature, and moving it to life. The words
of the Lord contradict such a meaning, when He speaks of Himself, "The
Son cannot of Himself do anything" (John 5:19); while many other
passages show the same, whereby we know that the Father is not the
Son. Careful examination shows that both of these opinions take
procession as meaning an outward act; hence neither of them affirms
procession as existing in God Himself; whereas, since procession
always supposes action, and as there is an outward procession
corresponding to the act tending to external matter, so there must be
an inward procession corresponding to the act remaining within the
agent. This applies most conspicuously to the intellect, the action of
which remains in the intelligent agent. For whenever we understand, by
the very fact of understanding there proceeds something within us,
which is a conception of the object understood, a conception issuing
from our intellectual power and proceeding from our knowledge of that
object. This conception is signified by the spoken word; and it is
called the word of the heart signified by the word of the voice.

As God