“ Consequently, that from which a man begins can be perfect in good or evil according to its genus, although it may be imperfect as regards the series of good or evil actions whereby a man progresses in good or evil. ”
 Thomas Aquinas, Summa Theologica (1274). copy citation

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“1: Movement both in good and in evil is made, for the most part, from imperfect to perfect, according as man progresses in good or evil: and yet in both cases, one man can begin from a greater (good or evil) than another man does. Consequently, that from which a man begins can be perfect in good or evil according to its genus, although it may be imperfect as regards the series of good or evil actions whereby a man progresses in good or evil. Reply Obj. 2: This argument considers the sin which is committed through certain malice, when it proceeds from the inclination of a habit.
Reply Obj. 3: If by impenitence we understand with Augustine (De Verb.” source