Objection 1. It would seem that wisdom is not in the intellect as its subject. For Augustine says (Ep. cxx) that "wisdom is the charity of God." Now charity is in the will as its subject, and not in the intellect, as stated above (Question 24, Article 1). Therefore wisdom is not in the intellect as its subject.
Objection 2. Further, it is written (Sirach 6:23): "The wisdom of doctrine is according to her name," for wisdom [sapientia] may be described as "sweet-tasting science [sapida scientia]," and this would seem to regard the appetite, to which it belongs to taste spiritual pleasure or sweetness. Therefore wisdom is in the appetite rather than in the intellect.
Objection 3. Further, the intellective power is sufficiently perfected by the gift of understanding. Now it is superfluous to require two things where one suffices for the purpose. Therefore wisdom is not in the intellect.
On the contrary, Gregory says (Moral. ii, 49) that "wisdom is contrary to folly." But folly is in the intellect. Therefore wisdom is also.
I answer that, As stated above (Article 1), wisdom denotes a certain rectitude of judgment according to the Eternal Law. Now rectitude of judgment is twofold: first, on account of perfect use of reason, secondly, on account of a certain connaturality with the matter about which one has to judge. Thus, about matters of chastity, a man after inquiring with his reason forms a right judgment, if he has learnt the science of morals, while he who has the habit of chastity judges of such matters by a kind of connaturality.
Accordingly it belongs to the wisdom that is an intellectual virtue to pronounce right judgment about Divine things after reason has made its inquiry, but it belongs to wisdom as a gift of the Holy Ghost to judge aright about them on account of connaturality with them: thus Dionysius says (Div. Nom. ii) that "Hierotheus is perfect in Divine things, for he not only learns, but is patient of, Divine things."
Now this sympathy or connaturality for Divine things is the result of charity, which unites us to God, according to 1 Corinthians 6:17: "He who is joined to the Lord, is one spirit." Consequently wisdom which is a gift, has its cause in the will, which cause is charity, but it has its essence in the intellect, whose act is to judge aright, as stated above (I-II, 14, 1).
Reply to Objection 1. Augustine is speaking of wisdom as to its cause, whence also wisdom [sapientia] takes its name, in so far as it denotes a certain sweetness [saporem].
Hence the Reply to the Second Objection is evident, that is if this be the true meaning of the text quoted. For, apparently this is not the case, because such an exposition of the text would only fit the Latin word for wisdom, whereas it does not apply to the Greek and perhaps not in other languages. Hence it would seem that in the text quoted wisdom stands for the renown of doctrine, for which it is praised by all.
Reply to Objection 3. The intellect exercises a twofold act, perception and judgment. The gift of understanding regards the former; the gift of wisdom regards the latter according to the Divine ideas, the gift of knowledge, according to human ideas.
Source: Summa Theologica (New Advent)