rstand how one angel speaks to another, we must consider that,
as we explained above (Q. 82, A. 4), when treating of the actions and
powers of the soul, the will moves the intellect to its operation.
Now an intelligible object is present to the intellect in three ways;
first, habitually, or in the memory, as Augustine says (De Trin. xiv,
6, 7); secondly, as actually considered or conceived; thirdly, as
related to something else. And it is clear that the intelligible
object passes from the first to the second stage by the command of
the will, and hence in the definition of habit these words occur,
"which anyone uses when he wills." So likewise the intelligible
object passes from the second to the third stage by the will; for by
the will the concept of the mind is ordered to something else, as,
for instance, either to the performing of an action, or to being made
known to another. Now when the mind turns itself to the actual
consideration of any habitual knowledge, then a person speaks to
himself; for the concept of the mind is called "the interior word."
And by the fact that the concept of the angelic mind is ordered to be
made known to another by the will of the angel himself, the concept
of one angel is made known to another; and in this way one angel
speaks to another; for to speak to another only means to make known
the mental concept to another.

Reply Obj. 1: Our mental concept is hidden by a twofold obstacle. The
first is in the will, which can retain the mental concept within, or
can direct it externally. In this way God alone can see the mind of
another, according to 1 Cor. 2:11: "What man knoweth the things of a
man, but the spirit of a man that is in him?" The other obstacle
whereby the mental concept is excluded from another one's knowledge,
comes from the body; and so it happens that even when the will
directs the concept of the mind to make itself known, it is not at
once make known to another; but some sensible sign must be used.
Gregory alludes to this fact when he says (Moral. ii): "To other eyes
we seem to stand aloof as it were behind the wall of the body; and
when we wish to make ourselves known, we go out as it were by the
door of the tongue to show what we really are." But an angel is under
no such obstacle, and so he can make his concept known to another at
once.

Reply Obj. 2: External speech, made by the voice, is a necessity for
us on account of the obstacle of the body. Hence it does not befi