Catechism of the Catholic Church

1865 Sin creates a proclivity to sin; it engenders vice by repetition of the same acts. This results in perverse inclinations which cloud conscience and corrupt the concrete judgment of good and evil. Thus sin tends to reproduce itself and reinforce itself, but it cannot destroy the moral sense at its root.

1866 Vices can be classified according to the virtues they oppose, or also be linked to the capital sins which Christian experience has distinguished, following St. John Cassian and St. Gregory the Great. They are called "capital" because they engender other sins, other vices. ¹³⁸ They are pride, avarice, envy, wrath, lust, gluttony, and sloth or acedia.

1867 The catechetical tradition also recalls that there are "sins that cry to heaven": the blood of Abel, ¹³⁹ the sin of the Sodomites, ¹⁴⁰ the cry of the people oppressed in Egypt, ¹⁴¹ the cry of the foreigner, the widow, and the orphan, ¹⁴² injustice to the wage earner. ¹⁴³

1868 Sin is a personal act. Moreover, we have a responsibility for the sins committed by others when we cooperate in them:

- by participating directly and voluntarily in them;

- by ordering, advising, praising, or approving them;

- by not disclosing or not hindering them when we have an obligation to do so;

- by protecting evil-doers.

1869 Thus sin makes men accomplices of one another and causes concupiscence, violence, and injustice to reign among them. Sins give rise to social situations and institutions that are contrary to the divine goodness. "Structures of sin" are the expression and effect of personal sins. They lead their victims to do evil in their turn. In an analogous sense, they constitute a "social sin." ¹⁴⁴

1870 "God has consigned all men to disobedience, that he may have mercy upon all" (Rom 11:32).

1871 Sin is an utterance, a deed, or a desire contrary to the eternal law (St. Augustine, Faust 22: PL 42, 418). It is an offense against God. It rises up against God in a disobedience contrary to the obedience of Christ.

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.

1 Lk 15:11-32.

2 GS 22.

3 Col 1:15; cf. 2 Cor 4:4.

4 Cf. GS 22.

5 GS 14 § 2.

6 GS 24 § 3.

7 GS 15 § 2.

8 GS 17.

9 GS 16.

10 GS 13 § 1.

11 GS 13 § 2.

12 Mt 5:3-12.

13 St. Augustine, De moribus eccl. 1, 3, 4: PL 32,1312.

14 St. Augustine, Conf. 10, 20: PL 32, 791.

15 St. Thomas Aquinas, Expos. in symb. apost. I.

16 Cf. Mt 4:17.

17 Mt 5:8; cf. I Jn 2; I Cor 13:12.

18 Mt 25:21-23.

19 Cf. Heb 4:7-11.

20 St. Augustine, De civ. Dei 22, 30, 5: PL 41,804.

21 2 Pet 1:4; cf. Jn 17:3.

22 Cf. Rom 8:18.

23 St. Irenaeus, Adv. haeres. 4, 20, 5: PG 7/1, 1034-1035.

24 John Henry Cardinal Newman, "Saintliness the Standard of Christian Principle," in Discourses to Mixed Congregations (London: Longmans, Green and Co., 1906) V, 89-90.

25 Cf. the parable of the sower: Mt 13:3-23.

26 GS 17; Sir 15:14.

27 St. Irenaeus, Adv. haeres. 4, 4, 3: PG 7/1, 983.

28 Cf. Rom 6:17.

29 Gen 3:13.

30 Cf. Gen 4:10.

31 Cf. 2 Sam 12:7-15.

32 Cf. DH 2 § 7.

33 CDF, instruction, Libertatis conscientia 13.

34 Gal 5:1.

35 Cf. Jn 8:32.

36 2 Cor 3:17.

37 Rom 8:21.

38 Roman Missal, 32nd Sunday, Opening Prayer: Omnipotens et misericors Deus, universa nobis adversantia propitiatus exclude, ut, mente et corpore pariter expediti, quae tua sunt liberis mentibus exsequamur.

39 Cf. Mt 6:24.

40 Cf. Mk 7:21.

41 St. Thomas Aquinas, STh I-II, 26, 4, corp. art.

42 Cf. St. Augustine, De Trin., 8, 3, 4: PL 42, 949-950.

43 St. Augustine, De civ. Dei 14, 7, 2: PL 41, 410.

44 St. Thomas Aquinas, STh I-II, 24, 1 corp. art.

45 Cf. St. Thomas Aquinas, STh I-II, 24, 3.

46 Ps 84:2.

47 GS 16.

48 Cf. Rom 2:14-16.

49 Cf. Rom 1:32.

50 John Henry Cardinal Newman, "Letter to the Duke of Norfolk," V, in Certain Difficulties felt by Anglicans in Catholic Teaching II (London: Longmans Green, 1885), 248.

51 St. Augustine, In ep Jo. 8, 9: PL 35, 2041.

52 I Jn 3:19-20.

53 DH 3 § 2.

54 Cf. Ps 119:105.

55 Cf. DH 14.

56 Mt 7:12; cf. Lk 6:31; Tob 4:15.

57 I Cor 8:12.

58 Rom 14:21.

59 GS 16.

60 I Tim 5; cf. 8:9; 2 Tim 3; I Pet 3:21; Acts 24:16.

61 GS 16.

62 Phil 4:8.

63 St. Gregory of Nyssa, De beatitudinibus, 1: PG 44, 1200D.

64 Wis 8:7.

65 Prov 14:15.

66 I Pet 4:7.

67 St. Thomas Aquinas, STh II-II, 47, 2.

68 Lev 19:15.

69 Col 4:1.

70 Ps 118:14.

71 Jn 16:33.

72 Sir 5:2; cf. 37:27-31.

73 Sir 18:30.

74 Titus 2:12.

75 St. Augustine, De moribus eccl. 1, 25, 46: PL 32, 1330-1331.

76 Cf. 2 Pet 1:4.

77 Cf. I Cor 13:13.

78 DV 5.

79 Rom 1:17; Gal 5:6.

80 Cf. Council of Trent (1547): DS 1545.

81 Jas 2:26.

82 LG 42; cf. DH 14.

83 Mt 10:32-33.

84 Heb 10:23.

85 Titus 3:6-7.

86 Cf. Gen 17:4-8; 22:1-18.

87 Rom 4:18.

88 Rom 5:5.

89 Heb 6:19-20.

90 I Thess 5:8.

91 Rom 12:12.

92 Cf. Rom 8:28-30; Mt 7:21.

93 Mt 10:22; cf. Council of Trent DS 1541.

94 I Tim 2:4.

95 St. Teresa of Avila, Excl. 15:3.

96 Cf. Jn 13:34.

97 Jn 13:1.

98 Jn 15:9, 12.

99 Jn 15:9-10; cf. Mt 22:40; Rom 13:8-10.

100 Rom 5:10.

101 Cf. Mt 5:44; Lk 10:27-37; Mk 9:37; Mt 25:40, 45.

102 I Cor 13:4-7.

103 I Cor 13:1-4.

104 I Cor 13:13.

105 Col 3:14.

106 Cf. I Jn 4:19.

107 St. Basil, Reg. fus. tract., prol. 3: PG 31, 896 B.

108 St. Augustine, In ep. Jo. 10, 4: PL 35, 2057.

109 Cf. Isa 11:1-2.

110 Ps 143:10.

111 Rom 8:14, 17.

112 Gal 5:22-23 (Vulg.).

113 Cf. Lk 15.

114 Mt 1:21.

115 Mt 26:28.

116 St. Augustine, Sermo 169, 11, 13: PL 38, 923.

117 I Jn 1:8-9.

118 Rom 5:20.

119 Rom 5:21.

120 John Paul II, DeV 31 § 2.

121 St. Augustine, Contra Faustum 22: PL 42, 418; St. Thomas Aquinas, STh I-II, 71, 6.

122 Ps 51:4.

123 Gen 3:5.

124 St. Augustine, De civ. Dei 14, 28: PL 41, 436.

125 Cf. Phil 2:6-9.

126 Cf. Jn 14:30.

127 Gal 5:19-21; cf. Rom 1:28-32; I Cor 9-10; Eph 5:3-5; Col 3:5-8; I Tim 9-10; 2 Tim 2-5.

128 Mt 15:19-20.

129 Cf. I Jn 5:16-17.

130 St. Thomas Aquinas, STh I-II, 88, 2, corp. art.

131 RP 17 § 12.

132 Mk 10:19.

133 Cf. Mk 3:5-6; Lk 16:19-31.

134 John Paul II, RP 17 § 9.

135 St. Augustine, In ep. Jo. 1, 6: PL 35, 1982.

136 Mk 3:29; cf. Mt 12:31; Lk 12:10.

137 Cf. John Paul II, DeV 46.

138 Cf. St. Gregory the Great, Moralia in Job, 31, 45: PL 76, 621A.

139 Cf. Gen 4:10.

140 Cf. Gen 18:20; 19:13.

141 Cf. Ex 3:7-10.

142 Cf. Ex 20:20-22.

143 Cf. Deut 24:14-15; Jas 5:4.

144 John Paul II, RP 16.