From The CCC Second edition,
1733 The more one does what is good, the freer one becomes. There is no true freedom except in the service of what is good and just. the choice to disobey and do evil is an abuse of freedom and leads to "the slavery of sin."28
1735 Imputability and responsibility for an action can be diminished or even nullified by ignorance, inadvertence, duress, fear, habit, inordinate attachments, and other psychological or social factors.
II. Good Acts and Evil Acts
1755 A morally good act requires the goodness of the object, of the end, and of the circumstances together. An evil end corrupts the action, even if the object is good in itself (such as praying and fasting “in order to be seen by men”).
The object of the choice can by itself vitiate an act in its entirety. There are some concrete acts - such as fornication - that it is always wrong to choose, because choosing them entails a disorder of the will, that is, a moral evil.
1756 It is therefore an error to judge the morality of human acts by considering only the intention that inspires them or the circumstances (environment, social pressure, duress or emergency, etc.) which supply their context. There are acts which, in and of themselves, independently of circumstances and intentions, are always gravely illicit by reason of their object; such as blasphemy and perjury, murder and adultery. One may not do evil so that good may result from it.
III. To Choose in Accord With Conscience
1789 Some rules apply in every case:
- One may never do evil so that good may result from it;
- the Golden Rule: "Whatever you wish that men would do to you, do so to them."56
- charity always proceeds by way of respect for one’s neighbor and his conscience: "Thus sinning against your brethren and wounding their conscience . . . you sin against Christ."57 Therefore "it is right not to . . . do anything that makes your brother stumble."58
IV. Erroneous Judgment
1792 Ignorance of Christ and his Gospel, bad example given by others, enslavement to one’s passions, assertion of a mistaken notion of autonomy of conscience, rejection of the Church’s authority and her teaching, lack of conversion and of charity: these can be at the source of errors of judgment in moral conduct.
By his sin, he condemns this woman. He has, knowingly or not wounded her conscience and made her stumble with him.
I. The Human Virtues
1809 Temperance is the moral virtue that moderates the attraction of pleasures and provides balance in the use of created goods. It ensures the will’s mastery over instincts and keeps desires within the limits of what is honorable. the temperate person directs the sensitive appetites toward what is good and maintains a healthy discretion: "Do not follow your inclination and strength, walking according to the desires of your heart."72 Temperance is often praised in the Old Testament: "Do not follow your base desires, but restrain your appetites."73 In the New Testament it is called “moderation” or “sobriety.” We ought "to live sober, upright, and godly lives in this world."74
1811 It is not easy for man, wounded by sin, to maintain moral balance. Christ’s gift of salvation offers us the grace necessary to persevere in the pursuit of the virtues. Everyone should always ask for this grace of light and strength, frequent the sacraments, cooperate with the Holy Spirit, and follow his calls to love what is good and shun evil.
II. The Definition of Sin
1849 Sin is an offense against reason, truth, and right conscience; it is failure in genuine love for God and neighbor caused by a perverse attachment to certain goods. It wounds the nature of man and injures human solidarity. It has been defined as "an utterance, a deed, or a desire contrary to the eternal law."121
1850 Sin is an offense against God: "Against you, you alone, have I sinned, and done that which is evil in your sight."122 Sin sets itself against God’s love for us and turns our hearts away from it. Like the first sin, it is disobedience, a revolt against God through the will to become "like gods,"123 knowing and determining good and evil. Sin is thus "love of oneself even to contempt of God."124 In this proud self-exaltation, sin is diametrically opposed to the obedience of Jesus, which achieves our salvation.125
1851 . . .The sacrifice of Christ secretly becomes the source from which the forgiveness of our sins will pour forth inexhaustibly.
Finally:
IV. The Gravity of Sin: Mortal and Venial Sin
1859 Mortal sin requires full knowledge and complete consent. It presupposes knowledge of the sinful character of the act, of its opposition to God’s law. It also implies a consent sufficiently deliberate to be a personal choice. Feigned ignorance and hardness of heart133 do not diminish, but rather increase, the voluntary character of a sin.
1860 Unintentional ignorance can diminish or even remove the imputability of a grave offense. But no one is deemed to be ignorant of the principles of the moral law, which are written in the conscience of every man. the promptings of feelings and passions can also diminish the voluntary and free character of the offense, as can external pressures or pathological disorders. Sin committed through malice, by deliberate choice of evil, is the gravest.
1864 "Whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin."136 There are no limits to the mercy of God, but anyone who deliberately refuses to accept his mercy by repenting, rejects the forgiveness of his sins and the salvation offered by the Holy Spirit.137 Such hardness of heart can lead to final impenitence and eternal loss.
I hope this helps. The full catechism is on the Vatican website under the “Secret Archives”.
