Having discussed the multiple meanings of “justice” and “to make/be made,” Contarini now moves on to treat the various senses in which the word “faith” (fides) can be taken. In the passage included below, there are four types of “faith.” First, Contarini has the distinction between the faith that is believed (fides quae creditur) and the faith by which belief occurs (fides qua creditur). The latter he subdivides into faith as habit (habitus) and as act (actus). The fourth type of faith he discusses is faith as trust (fiducia), which includes marital faith. This type of faith is connected to the keeping of promises: both the confidence that someone else will keep his promises (i.e., trust) and the pledge to keep one’s own (i.e., faithfulness or fidelity).
Now that these things have been set forth, let us proceed from “justification” to “faith.” “Faith” too is meant in multiple senses. For sometimes that which is believed is called “faith”, like that which is contained in the Athanasian Creed: “This is the catholic faith, which, unless anyone believes,” etc. Sometimes that habit [habitus] by which we believe these things that are handed down by God is called “faith”. Occasionally the act itself [actus ipse] by which we believe is accustomed to be called “faith”. This act, although it is drawn forth from the intellect, is nevertheless commanded by the will. Therefore the Apostle says, “to the obedience of faith.” For, truly, we believe because we want to obey God. “Faith” is also called “trust” [fiducia], because we have confidence in the promise made to us by someone. In this way we say “to keep faith” and “to break faith.” Cicero says in the first book of On Duties that this [i.e., faith as fiducia] was meant as though it were [that] by which what has been said is done [in reality], and he reckons this “faith” as a part of justice. Thus “marital faith,” by which each of the spouses pledges faith mutually to the other [and] believes and has confidence in the promise of the other in turn, is reckoned among the three goods of marriage. (De Iustificatione, p. 589)