he end, it has not yet obtained the gift of
understanding, however much the Holy Ghost may have enlightened it in
regard to other truths that are preambles to the faith.

Now to have a right estimate about the last end one must not be in
error about the end, and must adhere to it firmly as to the greatest
good: and no one can do this without sanctifying grace; even as in
moral matters a man has a right estimate about the end through a habit
of virtue. Therefore no one has the gift of understanding without
sanctifying grace.

Reply Obj. 1: By understanding Augustine means any kind of
intellectual light, that, however, does not fulfil all the conditions
of a gift, unless the mind of man be so far perfected as to have a
right estimate about the end.

Reply Obj. 2: The understanding that is requisite for prophecy, is a
kind of enlightenment of the mind with regard to the things revealed
to the prophet: but it is not an enlightenment of the mind with
regard to a right estimate about the last end, which belongs to the
gift of understanding.

Reply Obj. 3: Faith implies merely assent to what is proposed but
understanding implies a certain perception of the truth, which
perception, except in one who has sanctifying grace, cannot regard
the end, as stated above. Hence the comparison fails between
understanding and faith.
_______________________

SIXTH ARTICLE [II-II, Q. 8, Art. 6]

Whether the Gift of Understanding Is Distinct from the Other Gifts?

Objection 1: It would seem that the gift of understanding is not
distinct from the other gifts. For there is no distinction between
things whose opposites are not distinct. Now "wisdom is contrary to
folly, understanding is contrary to dulness, counsel is contrary to
rashness, knowledge is contrary to ignorance," as Gregory states
(Moral. ii, 49). But there would seem to be no difference between
folly, dulness, ignorance and rashness. Therefore neither does
understanding differ from the other gifts.

Obj. 2: Further, the intellectual virtue of understanding differs
from the other intellectual virtues in that it is proper to it to be
about self-evident principles. But the gift of understanding is not
about any self-evident principles, since the natural habit of first
principles suffices in respect of those matters which are naturally
self-evident: while faith is sufficient in respect of such things as
are supernatural, since the articles of faith are like first
principles