Chapter I. On Faith

186. • Faith in general is assent on account of the authority of one speaking. More precisely for our matter, Faith, insofar as it is a virtue, is defined: A supernatural, infused habit inclining the intellect to assent firmly to truths revealed by God and proposed by the Church, on account of the authority of God revealing. But insofar as it is an act, it is called the firmest assent given to things revealed by God on account of the authority of God revealing. - St. Lig. n. 2.

Faith is 1º habitual or actual, according as it is a habit or an act.

2º Explicit or implicit by reason of the object, according as this is expressed and unfolded in itself, or only contained in another. Thus, for example, if you say: I believe in the Most Holy Trinity, you elicit an act of Faith explicit in that mystery. But if you say: I believe all things which the Church teaches are to be believed, you elicit an act of Faith implicit in the several revealed dogmas.

3º Formal or virtual, according as faith either is actually elicited, or, persevering in the mind without advertence, by its force influences actions.

4º Formed, or living, or unformed, or dead, according as it is joined, or not, with the works of Charity.

Sins opposed to Faith are 1º infidelity, or the lack of Faith in unbaptized men; 2º heresy, or a pertinacious error in one baptized against a truth of Faith proposed by the Church.

Infidelity, or heresy, is called negative or material in him who labors under invincible ignorance, or to whom the true Faith has not been sufficiently proposed.

The treatment must be chiefly 1º concerning the necessity, 2º concerning the object of Faith.