Cap. 6 Arg. 8: Proper vivifying grace—faith, conversion, regeneration; Augustine's colors
Other supernatural gifts actually bring the state of salvation: a good will, faith, conversion, regeneration—in short, what belongs only to people grafted into Christ and reconciled to God. Those, Augustine says, deserve the name "grace of Christ" in the proper sense. Preaching and knowledge of Christian doctrine he refers to that proper grace only so far as they help produce and advance it. In On the Grace of Christ he makes the point expressly: the name does not mean mere lighting of the mind or stirring of the will, but the gift of faith itself and of a good will. He paints that grace in bright colors—the grace by which we are justified from iniquity and saved from weakness; a grace we barely share with the ungodly, but the grace by which we are children of God. Now for the Fathers' own words.
Latin
Sunt etiam alia dona supernaturalia quae statum salutis habentibus apportant, qualia sunt bona Voluntas, Fides, Conversio, Regeneratio; ut dicam brevi, ea quae solis hominibus in Christum insertis et Deo reconciliatis conveniunt. Atque haec ea sunt quae Augustinus appellatione gratiae Christi proprie designanda arbitratur: priora autem illa, scilicet praedicationem et cognitionem doctrinae Christianae, ad hanc Christi gratiam proprie dictam eatenus reducit, quatenus inserviunt eidem producendae et promovendae. In libro De gratia Christi id ex professo agit ut ostendat, hoc nomine venire non illuminationem mentis aut excitationem voluntatis, sed ipsam fidem et bonae voluntatis donationem, cap. 10, 47; Epist. 99. Hanc gratiam Christi vivis coloribus depingit atque appellat, gratiam qua justificamur ab iniquitate, et qua salvamur ab infirmitate; gratiam quam cum impiis minime communem habemus, sed eam qua filii Dei sumus. Jam Patrum testimonia audiamus.