How can a person be delivered from a serious sin and reunited with God?
In order to heal the break with God that is caused by a serious sin, a Catholic Christian must be reconciled with God through confession.
What are vices?
Vices are negative habits that deaden and dull the conscience, incline a person to evil, and habitually prepare him for sin.
Human vices are found in connection with the capital sins of pride, avarice, envy, anger, lust, gluttony, and sloth (or acedia, spiritual boredom).
Are we responsible for the sins of other people?
No, we are not responsible for other people's sins, unless we are guilty of misleading or seducing another person to sin or of cooperating in it or of encouraging someone else to sin or of neglecting to offer a timely warning or our help. (YOUCAT questions 317-319)
Dig Deeper: CCC section (1865-1868) and other references here.
Part 3: Life in Christ (1691 - 2557)
Section 1: Man's Vocation — Life in the Spirit (1699 - 2051)
Chapter 1: The Dignity of the Human Person (1700 - 1876)
Article 8: Sin (1846 - 1876)
V. THE PROLIFERATION OF SIN ⇡
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.
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.
138.
Cf. St. Gregory the Great, Moralia in Job, 31,45:PL 76,621A.
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
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.
Sin is a personal act. Moreover, we have a responsibility for the sins committed by others when we cooperate in them: