HKB
both an act of reason, and an act of the concupiscible faculty, even as the act of faith requires an act of the will, and an act of the intellect.
Reply Obj. 1: The truth is itself the good of the intellect, since it is its perfection: and consequently faith has a relation to some good in so far as it directs the intellect to the true. Furthermore, it has a relation to the good considered as the object of the will, inasmuch as it is formed by charity.
Reply Obj. 2: The faith of which the Philosopher speaks is based on human reasoning in a conclusion which does not follow, of necessity, from its premisses; and which is subject to be false: hence such like faith is not a virtue. On the other hand, the faith of which we are speaking is based on the Divine Truth, which is infallible, and consequently its object cannot be anything false; so that faith of this kind can be a virtue.
Reply Obj. 3: Living and lifeless faith do not differ specifically, as though they belonged to different species. But they differ as perfect and imperfect within the same species. Hence lifeless faith, being imperfect, does not satisfy the conditions of a perfect virtue, for "virtue is a kind of perfection" (Phys. vii, text. 18).
Reply Obj. 4: Some say that faith which is numbered among the gratuitous graces is lifeless faith. But this is said without reason, since the gratuitous graces, which are mentioned in that passage, are not common to all the members of the Church: wherefore the Apostle says: "There are diversities of graces," and again, "To one is given" this grace and "to another" that. Now lifeless faith is common to all members of the Church, because its lifelessness is not part of its substance, if we consider it as a gratuitous gift. We must, therefore, say that in that passage, faith denotes a certain excellency of faith, for instance, "constancy in faith," according to a gloss, or the "word of faith."
Faith is numbered among the fruits, in so far as it gives a certain pleasure in its act by reason of its certainty, wherefore the gloss on the fifth chapter to the Galatians, where the fruits are enumerated, explains faith as being "certainty about the unseen."
SIXTH ARTICLE [II-II, Q. 4, Art. 6]
Whether Faith Is One Virtue?
Objection 1: It would seem that faith is not one. For just as faith is a gift of God according to Eph. 2:8, so also wisdom and knowledge are numbered among God's gifts according to Isa. 11:2. Now wisdom and knowledge differ in this, that wisdom is about eternal things, and knowledge about temporal things, as Augustine states (De Trin. xii, 14, 15). Since, then, faith is about eternal things, and also about some temporal things, it seems that faith is not one virtue, but divided into several parts.
Obj. 2: Further, confession is an act of faith, as stated above (Q. 3, A. 1). Now confession of faith is not one and the same for all: since what we confess as past, the fathers of old confessed as yet to come, as appears from Isa. 7:14: "Behold a virgin shall conceive." Therefore faith is not one.
Obj. 3: Further, faith is common to all believers in Christ. But one accident cannot be in many subjects. Therefore all cannot have one faith.
On the contrary, The Apostle says (Eph. 4:5): "One Lord, one faith."