Objection 1. It would seem that the acts of the moral virtues do not all pertain to the active life. For seemingly the active life regards only our relations with other persons: hence Gregory says (Hom. xiv in Ezech.) that "the active life is to give bread to the hungry," and after mentioning many things that regard our relations with other people he adds finally, "and to give to each and every one whatever he needs." Now we are directed in our relations to others, not by all the acts of moral virtues, but only by those of justice and its parts, as stated above (58, 2 and 8; I-II, 60, 2 and 3). Therefore the acts of the moral virtues do not all pertain to the active life.
Objection 2. Further, Gregory says (Hom. xiv in Ezech.) that Lia who was blear-eyed but fruitful signifies the active life: which "being occupied with work, sees less, and yet since it urges one's neighbor both by word and example to its imitation it begets a numerous offspring of good deeds." Now this would seem to belong to charity, whereby we love our neighbor, rather than to the moral virtues. Therefore seemingly the acts of moral virtue do not pertain to the active life.
Objection 3. Further, as stated above (Question 180, Article 2), the moral virtues dispose one to the contemplative life. Now disposition and perfection belong to the same thing. Therefore it would seem that the moral virtues do not pertain to the active life.
On the contrary, Isidore says (De Summo Bono iii, 15): "In the active life all vices must first of all be extirpated by the practice of good works, in order that in the contemplative life the mind's eye being purified one may advance to the contemplation of the Divine light." Now all vices are not extirpated save by acts of the moral virtues. Therefore the acts of the moral virtues pertain to the active life.
I answer that, As stated above (Question 179, Article 1) the active and the contemplative life differ according to the different occupations of men intent on different ends: one of which occupations is the consideration of the truth; and this is the end of the contemplative life, while the other is external work to which the active life is directed.
Now it is evident that the moral virtues are directed chiefly, not to the contemplation of truth but to operation. Wherefore the Philosopher says (Ethic. ii, 4) that "for virtue knowledge is of little or no avail." Hence it is clear that the moral virtues belong essentially to the active life; for which reason the Philosopher (Ethic. x, 8) subordinates the moral virtues to active happiness.
Reply to Objection 1. The chief of the moral virtues is justice by which one man is directed in his relations towards another, as the Philosopher proves (Ethic. v, 1). Hence the active life is described with reference to our relations with other people, because it consists in these things, not exclusively, but principally.
Reply to Objection 2. It is possible, by the acts of all the moral virtues, for one to direct one's neighbor to good by example: and this is what Gregory here ascribes to the active life.
Reply to Objection 3. Even as the virtue that is directed to the end of another virtue passes, as it were, into the species of the latter virtue, so again when a man makes use of things pertaining to the active life, merely as dispositions to contemplation, such things are comprised under the contemplative life. On the other hand, when we practice the works of the moral virtues, as being good in themselves, and not as dispositions to the contemplative life, the moral virtues belong to the active life.
It may also be replied, however, that the active life is a disposition to the contemplative life.
Source: Summa Theologica (New Advent)