| 1872 Sin is an act contrary to reason. It wounds man's nature and injures human solidarity. |
| 1873 The root of all sins lies in man's heart. The kinds and the gravity of sins are determined principally by their objects. |
| 1874 To choose deliberately - that is, both knowing it and willing it - something gravely contrary to the divine law and to the ultimate end of man is to commit a mortal sin. This destroys in us the charity without which eternal beatitude is impossible. Unrepented, it brings eternal death. |
| 1875 Venial sin constitutes a moral disorder that is reparable by charity, which it allows to subsist in us. |
| 1876 The repetition of sins - even venial ones - engenders vices, among which are the capital sins. |