Treatise: On Sins in General

410. Object of the treatise. - Moral theology treats of human acts by which we come to the end, beatitude. They are those acts which are conformed to the dictate of right conscience and to the eternal law. But there are also human acts which are not conformed to the law of God or to the dictate of right conscience, by which we do not come to the end, and which are called sins. Hence, after the treatises on the end, on human acts, and on their rules, namely, on conscience and on law, the consideration of evil acts or sins rightly follows.

411. The treatise is divided into three parts:

The first part treats of sin according to itself:

1. of the essence of sin; 2) of the distinction of sins, a) specific, b) numerical; 3) of the comparison and gravity of sins; 4) of the subject of sin, where internal sins are treated.

The second part treats of the causes of sins:

1. of interior causes: a) of ignorance on the part of reason, b) of passion on the part of the sensitive appetite, c) of malice on the part of the will;

2. of exterior causes: a) of God permitting, b) of the devil tempting, c) of man cooperating;

3. of sin which is the cause of another sin, namely, of the mode by which one sin causes another, and of capital sins.

The third part treats of the effects of sin:

1. of the diminution of the good of nature; 2) of stain or guilt of fault; 3) of guilt of punishment; 4) of mortal and venial sin, which are distinguished according to diverse effects: a) of the distinction of mortal sin from venial, b) of its gravity, c) of the conditions required for it, d) of the division of mortal and venial sins, e) of their conversion, f) of venial sin according to itself.

412. Importance of the treatise. - The treatise is of the greatest importance, because it applies the abstract general principles concerning human acts more determinately and concretely to sins, which above all are to be avoided by each one, and are to be estimated and judged in others by the priest and confessor.

1. The following can usefully be consulted: St. Thomas, Quaestiones Disputatae de Malo 1, 2, 3, 7; and I-II, q. 71-89 with the commentaries of Cajetan and Billuart; St. Alphonsus, Theologia Moralis, book V; Reiffenstuel, Theologia Moralis; Ferraris, Prompta Bibliotheca; Ballerini-Palmieri, Opus theologicum morale, vol. I; Billot, De peccato personali et originali; Theologia Mechliniensis, Tractatus de Peccatis, edited by St. Carton de Wiart; Lumbreras, De Vitiis et Peccatis; Deman, article "Peche," in Dictionnaire de Theologie; and manuals known to all, such as Van der Velden, Haine, Aertnijs, Marc, Lehmkuhl, Genicot, Noldin, Tanquerey, Prummer, and Vermeersch.