LIFE IN CHRIST
1691 "Christian, recognize your dignity and, now that you share in God's own nature, do not return to your former base condition by sinning. Remember who is your head and of whose body you are a member. Never forget that you have been rescued from the power of darkness and brought into the light of the Kingdom of God." [St. Leo the Great Sermo 22 in nat. Dom., 3: PL 54, 192C] 
1692 The Symbol of the faith confesses the greatness of God's gifts to man in his work of creation, and even more in redemption and sanctification. What faith confesses, the sacraments communicate: by the sacraments of rebirth, Christians have become "children of God," [Jn 1:12; 1 Jn 3:1] "partakers of the divine nature." [2 Pet 1:4] Coming to see in the faith their new dignity, Christians are called to lead henceforth a life "worthy of the gospel of Christ." [Phil 1:27] They are made capable of doing so by the grace of Christ and the gifts of his Spirit, which they receive through the sacraments and through prayer.
1693 Christ Jesus always did what was pleasing to the Father, [Cf. Jn 8:29] and always lived in perfect communion with him. Likewise Christ's disciples are invited to live in the sight of the Father "who sees in secret," [Mt 6:6] in order to become "perfect as your heavenly Father is perfect." [Mt 5:48]
1694 Incorporated into Christ by Baptism, Christians are "dead to sin and alive to God in Christ Jesus" and so participate in the life of the Risen Lord. [Rom 6:11 and cf. 6:5; cf. Col 2:12] Following Christ and united with him, [Cf. Jn 15:5] Christians can strive to be "imitators of God as beloved children, and walk in love" [Eph 5:1-2] by conforming their thoughts, words and actions to the "mind... which is yours in Christ Jesus," [Phil 2:5] and by following his example. [Cf. Jn 13:12-16] 
1695 "Justified in the name of the Lord Jesus Christ and in the Spirit of our God," [2 Cor 6:11] "sanctified... [and] called to be saints," [1 Cor 1:2] Christians have become the temple of the Holy Spirit. [Cf. 1 Cor 6:19] This "Spirit of the Son" teaches them to pray to the Father [Cf. Gal 4:6] and, having become their life, prompts them to act so as to bear "the fruit of the Spirit" [Gal 5:22, 25] by charity in action. Healing the wounds of sin, the Holy Spirit renews us interiorly through a spiritual transformation. [Cf. Eph 4:23] He enlightens and strengthens us to live as "children of light" through "all that is good and right and true." [Eph 5:8, 9]
1696 The way of Christ "leads to life"; a contrary way "leads to destruction." [Mt 7:13; cf. Deut 30: 15-20] The Gospel parable of the two ways remains ever present in the catechesis of the Church; it shows the importance of moral decisions for our salvation: "There are two ways, the one of life, the other of death; but between the two, there is a great difference." [Didache 1, 1: SCh 248, 140] 
1697 Catechesis has to reveal in all clarity the joy and the demands of the way of Christ. [Cf. John Paul II, CT 29] Catechesis for the "newness of life" [Rom 6:4] in him should be:
- a catechesis of the Holy Spirit, the interior Master of life according to Christ, a gentle guest and friend who inspires, guides, corrects, and strengthens this life; [737 ff.]
- a catechesis of grace, for it is by grace that we are saved and again it is by grace that our works can bear fruit for eternal life; [1938 ff.]
- a catechesis of the beatitudes, for the way of Christ is summed up in the beatitudes, the only path that leads to the eternal beatitude for which the human heart longs; [1716 ff.]
- a catechesis of sin and forgiveness, for unless man acknowledges that he is a sinner he cannot know the truth about himself, which is a condition for acting justly; and without the offer of forgiveness he would not be able to bear this truth; [1846 ff.]
- a catechesis of the human virtues which causes one to grasp the beauty and attraction of right dispositions towards goodness; [1803 ff.]
- a catechesis of the Christian virtues of faith, hope, and charity, generously inspired by the example of the saints; [1812 ff.]
- a catechesis of the twofold commandment of charity set forth in the Decalogue; [2067 ff.]
- an ecclesial catechesis, for it is through the manifold exchanges of "spiritual goods" in the "communion of saints" that Christian life can grow, develop, and be communicated. [946 ff.]
1698 The first and last point of reference of this catechesis will always be Jesus Christ himself, who is "the way, and the truth, and the life." [Jn 14:6] It is by looking to him in faith that Christ's faithful can hope that he himself fulfills his promises in them, and that, by loving him with the same love with which he has loved them, they may perform works in keeping with their dignity: 
I ask you to consider that our Lord Jesus Christ is your true head, and that you are one of his members. He belongs to you as the head belongs to its members; all that is his is yours: his spirit, his heart, his body and soul, and all his faculties. You must make use of all these as of your own, to serve, praise, love, and glorify God. You belong to him, as members belong to their head. And so he longs for you to use all that is in you, as if it were his own, for the service and glory of the Father. [St. John Eudes, Tract. de admirabili corde Jesu, 1, 5]
For to me, to live is Christ. [Phil 1:21]
LIFE IN THE SPIRIT
1699 Life in the Holy Spirit fulfills the vocation of man (chapter one). This life is made up of divine charity and human solidarity (chapter two). It is graciously offered as salvation (chapter three).
THE DIGNITY OF THE HUMAN PERSON
1700 The dignity of the human person is rooted in his creation in the image and likeness of God (article 1); it is fulfilled in his vocation to divine beatitude (article 2). It is essential to a human being freely to direct himself to this fulfillment (article 3). By his deliberate actions (article 4), the human person does, or does not, conform to the good promised by God and attested by moral conscience (article 5). Human beings make their own contribution to their interior growth; they make their whole sentient and spiritual lives into means of this growth (article 6). With the help of grace they grow in virtue (article 7), avoid sin, and if they sin they entrust themselves as did the prodigal son [Lk 15:11-32] to the mercy of our Father in heaven (article 8). In this way they attain to the perfection of charity. [356, 1439]
MAN: THE IMAGE OF GOD
1701 "Christ,... in the very revelation of the mystery of the Father and of his love, makes man fully manifest to himself and brings to light his exalted vocation." [GS 22] It is in Christ, "the image of the invisible God," [Col 1:15; cf. 2 Cor 4:4] that man has been created "in the image and likeness" of the Creator. It is in Christ, Redeemer and Savior, that the divine image, disfigured in man by the first sin, has been restored to its original beauty and ennobled by the grace of God. [Cf. GS 22] 
1702 The divine image is present in every man. It shines forth in the communion of persons, in the likeness of the unity of the divine persons among themselves (cf. chapter two). 
1703 Endowed with "a spiritual and immortal" soul, [GS 14 § 2] the human person is "the only creature on earth that God has willed for its own sake." [GS 24 § 3] From his conception, he is destined for eternal beatitude. [363, 2258]
1704 The human person participates in the light and power of the divine Spirit. By his reason, he is capable of understanding the order of things established by the Creator. By free will, he is capable of directing himself toward his true good. He finds his perfection "in seeking and loving what is true and good." [GS 15 § 2] [339, 30]
1705 By virtue of his soul and his spiritual powers of intellect and will, man is endowed with freedom, an "outstanding manifestation of the divine image." [GS 17] 
1706 By his reason, man recognizes the voice of God which urges him "to do what is good and avoid what is evil." [GS 16] Everyone is obliged to follow this law, which makes itself heard in conscience and is fulfilled in the love of God and of neighbor. Living a moral life bears witness to the dignity of the person. 
1707 "Man, enticed by the Evil One, abused his freedom at the very beginning of history." [GS 13 § 1] He succumbed to temptation and did what was evil. He still desires the good, but his nature bears the wound of original sin. He is now inclined to evil and subject to error: 
Man is divided in himself. As a result, the whole life of men, both individual and social, shows itself to be a struggle, and a dramatic one, between good and evil, between light and darkness. [GS 13 § 2]
1708 By his Passion, Christ delivered us from Satan and from sin. He merited for us the new life in the Holy Spirit. His grace restores what sin had damaged in us. 
1709 He who believes in Christ becomes a son of God. This filial adoption transforms him by giving him the ability to follow the example of Christ. It makes him capable of acting rightly and doing good. In union with his Savior, the disciple attains the perfection of charity which is holiness. Having matured in grace, the moral life blossoms into eternal life in the glory of heaven. [1265, 1050]
1710 "Christ... makes man fully manifest to man himself and brings to light his exalted vocation" (GS 22 § 1).
1711 Endowed with a spiritual soul, with intellect and with free will, the human person is from his very conception ordered to God and destined for eternal beatitude. He pursues his perfection in "seeking and loving what is true and good" (GS 15 § 2).
1712 In man, true freedom is an "outstanding manifestation of the divine image" (GS 17).
1713 Man is obliged to follow the moral law, which urges him "to do what is good and avoid what is evil" (cf. GS 16). This law makes itself heard in his conscience.
1714 Man, having been wounded in his nature by original sin, is subject to error and inclined to evil in exercising his freedom.
1715 He who believes in Christ has new life in the Holy Spirit. The moral life, increased and brought to maturity in grace, is to reach its fulfillment in the glory of heaven.
OUR VOCATION TO BEATITUDE
I. THE BEATITUDES
1716 The Beatitudes are at the heart of Jesus' preaching. They take up the promises made to the chosen people since Abraham. The Beatitudes fulfill the promises by ordering them no longer merely to the possession of a territory, but to the Kingdom of heaven:
Blessed are the poor in spirit, for theirs is the kingdom of heaven. 
Blessed are those who mourn, for they shall be comforted.
Blessed are the meek, for they shall inherit the earth.
Blessed are those who hunger and thirst for righteousness, for they shall be satisfied.
Blessed are the merciful, for they shall obtain mercy.
Blessed are the pure in heart, for they shall see God.
Blessed are the peacemakers, for they shall be called sons of God.
Blessed are those who are persecuted for righteousness' sake, for theirs is the kingdom of heaven.
Blessed are you when men revile you and persecute you and utter all kinds of evil against you falsely on my account.
Rejoice and be glad, for your reward is great in heaven. [Mt 5:3-12]
1717 The Beatitudes depict the countenance of Jesus Christ and portray his charity. They express the vocation of the faithful associated with the glory of his Passion and Resurrection; they shed light on the actions and attitudes characteristic of the Christian life; they are the paradoxical promises that sustain hope in the midst of tribulations; they proclaim the blessings and rewards already secured, however dimly, for Christ's disciples; they have begun in the lives of the Virgin Mary and all the saints. [459, 1820]
II. THE DESIRE FOR HAPPINESS
1718 The Beatitudes respond to the natural desire for happiness. This desire is of divine origin: God has placed it in the human heart in order to draw man to the One who alone can fulfill it: [27, 1024]
We all want to live happily; in the whole human race there is no one who does not assent to this proposition, even before it is fully articulated. [St. Augustine, De moribus eccl. 1, 3, 4: PL 32,1312]
How is it, then, that I seek you, Lord? Since in seeking you, my God, I seek a happy life, let me seek you so that my soul may live, for my body draws life from my soul and my soul draws life from you. [St. Augustine, Conf. 10, 20: PL 32, 791] 
God alone satisfies. [St. Thomas Aquinas, Expos. in symb. apost. I]
1719 The Beatitudes reveal the goal of human existence, the ultimate end of human acts: God calls us to his own beatitude. This vocation is addressed to each individual personally, but also to the Church as a whole, the new people made up of those who have accepted the promise and live from it in faith. 
III. CHRISTIAN BEATITUDE
1720 The New Testament uses several expressions to characterize the beatitude to which God calls man: 
- the coming of the Kingdom of God; [Cf. Mt 4:17]
- the vision of God: "Blessed are the pure in heart, for they shall see God" [Mt 5:8; cf. 1 Jn 2; 1 Cor 13:12]
- entering into the joy of the Lord; [Mt 25:21-23]
- entering into God's rest: [Cf. Heb 4:7-11]
There we shall rest and see, we shall see and love, we shall love and praise. Behold what will be at the end without end. For what other end do we have, if not to reach the kingdom which has no end? [St. Augustine, De civ. Dei 22, 30, 5: PL 41,804]
1721 God put us in the world to know, to love, and to serve him, and so to come to paradise. Beatitude makes us "partakers of the divine nature" and of eternal life. [2 Pet 1:4; cf. Jn 17:3] With beatitude, man enters into the glory of Christ [Cf. Rom 8:18] and into the joy of the Trinitarian life. 
1722 Such beatitude surpasses the understanding and powers of man. It comes from an entirely free gift of God: whence it is called supernatural, as is the grace that disposes man to enter into the divine joy. 
"Blessed are the pure in heart, for they shall see God." It is true, because of the greatness and inexpressible glory of God, that "man shall not see me and live," for the Father cannot be grasped. But because of God's love and goodness toward us, and because he can do all things, he goes so far as to grant those who love him the privilege of seeing him.... For "what is impossible for men is possible for God." [St. Irenaeus, Adv. haeres. 4,20,5: PG 7/1, 1034-1035] 
1723 The beatitude we are promised confronts us with decisive moral choices. It invites us to purify our hearts of bad instincts and to seek the love of God above all else. It teaches us that true happiness is not found in riches or well-being, in human fame or power, or in any human achievement - however beneficial it may be - such as science, technology, and art, or indeed in any creature, but in God alone, the source of every good and of all love: [2519, 227]
All bow down before wealth. Wealth is that to which the multitude of men pay an instinctive homage. They measure happiness by wealth; and by wealth they measure respectability.... It is a homage resulting from a profound faith ... that with wealth he may do all things. Wealth is one idol of the day and notoriety is a second.... Notoriety, or the making of a noise in the world - it may be called "newspaper fame" - has come to be considered a great good in itself, and a ground of veneration. [John Henry Cardinal Newman, "Saintliness the Standard of Christian Principle," in Discourses to Mixed Congregations (London: Longmans, Green and Co., 1906) V, 89-90]
1724 The Decalogue, the Sermon on the Mount, and the apostolic catechesis describe for us the paths that lead to the Kingdom of heaven. Sustained by the grace of the Holy Spirit, we tread them, step by step, by everyday acts. By the working of the Word of Christ, we slowly bear fruit in the Church to the glory of God. [Cf. the parable of the sower: Mt 13:3-23]
1725 The Beatitudes take up and fulfill God's promises from Abraham on by ordering them to the Kingdom of heaven. They respond to the desire for happiness that God has placed in the human heart.
1726 The Beatitudes teach us the final end to which God calls us: the Kingdom, the vision of God, participation in the divine nature, eternal life, filiation, rest in God.
1727 The beatitude of eternal life is a gratuitous gift of God. It is supernatural, as is the grace that leads us there.
1728 The Beatitudes confront us with decisive choices concerning earthly goods; they purify our hearts in order to teach us to love God above all things.
1729 The beatitude of heaven sets the standards for discernment in the use of earthly goods in keeping with the law of God.
1730 God created man a rational being, conferring on him the dignity of a person who can initiate and control his own actions. "God willed that man should be 'left in the hand of his own counsel,' so that he might of his own accord seek his Creator and freely attain his full and blessed perfection by cleaving to him." [GS 17; Sir 15:14] Man is rational and therefore like God; he is created with free will and is master over his acts. [St. Irenaeus, Adv. haeres. 4, 4, 3: PG 7/1, 983] 
I. FREEDOM AND RESPONSIBILITY
1731 Freedom is the power, rooted in reason and will, to act or not to act, to do this or that, and so to perform deliberate actions on one's own responsibility. By free will one shapes one's own life. Human freedom is a force for growth and maturity in truth and goodness; it attains its perfection when directed toward God, our beatitude. 
1732 As long as freedom has not bound itself definitively to its ultimate good which is God, there is the possibility of choosing between good and evil, and thus of growing in perfection or of failing and sinning. This freedom characterizes properly human acts. It is the basis of praise or blame, merit or reproach. [396, 1849, 2006]
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." [Cf. Rom 6:17] 
1734 Freedom makes man responsible for his acts to the extent that they are voluntary. Progress in virtue, knowledge of the good, and ascesis enhance the mastery of the will over its acts. [1036, 1804]
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. 
1736 Every act directly willed is imputable to its author: 
Thus the Lord asked Eve after the sin in the garden: "What is this that you have done?" [Gen 3:13] He asked Cain the same question. [Cf. Gen 4:10] The prophet Nathan questioned David in the same way after he committed adultery with the wife of Uriah and had him murdered. [Cf. 2 Sam 12:7-15]
An action can be indirectly voluntary when it results from negligence regarding something one should have known or done: for example, an accident arising from ignorance of traffic laws.
1737 An effect can be tolerated without being willed by its agent; for instance, a mother's exhaustion from tending her sick child. A bad effect is not imputable if it was not willed either as an end or as a means of an action, e.g., a death a person incurs in aiding someone in danger. For a bad effect to be imputable it must be foreseeable and the agent must have the possibility of avoiding it, as in the case of manslaughter caused by a drunken driver. 
1738 Freedom is exercised in relationships between human beings. Every human person, created in the image of God, has the natural right to be recognized as a free and responsible being. All owe to each other this duty of respect. The right to the exercise of freedom, especially in moral and religious matters, is an inalienable requirement of the dignity of the human person. This right must be recognized and protected by civil authority within the limits of the common good and public order. [Cf. DH 2 § 7] [2106, 2109]
II. HUMAN FREEDOM IN THE ECONOMY OF SALVATION
1739 Freedom and sin. Man's freedom is limited and fallible. In fact, man failed. He freely sinned. By refusing God's plan of love, he deceived himself and became a slave to sin. This first alienation engendered a multitude of others. From its outset, human history attests the wretchedness and oppression born of the human heart in consequence of the abuse of freedom. [387, 401]
1740 Threats to freedom. The exercise of freedom does not imply a right to say or do everything. It is false to maintain that man, "the subject of this freedom," is "an individual who is fully self-sufficient and whose finality is the satisfaction of his own interests in the enjoyment of earthly goods." [CDF, instruction, Libertatis conscientia 13] Moreover, the economic, social, political, and cultural conditions that are needed for a just exercise of freedom are too often disregarded or violated. Such situations of blindness and injustice injure the moral life and involve the strong as well as the weak in the temptation to sin against charity. By deviating from the moral law man violates his own freedom, becomes imprisoned within himself, disrupts neighborly fellowship, and rebels against divine truth. [2108, 1887]
1741 Liberation and salvation. By his glorious Cross Christ has won salvation for all men. He redeemed them from the sin that held them in bondage. "For freedom Christ has set us free." [Gal 5:1] In him we have communion with the "truth that makes us free." [Cf. In 8:32] The Holy Spirit has been given to us and, as the Apostle teaches, "Where the Spirit of the Lord is, there is freedom." [2 Cor 17] Already we glory in the "liberty of the children of God." [Rom 8:21] 
1742 Freedom and grace. The grace of Christ is not in the slightest way a rival of our freedom when this freedom accords with the sense of the true and the good that God has put in the human heart. On the contrary, as Christian experience attests especially in prayer, the more docile we are to the promptings of grace, the more we grow in inner freedom and confidence during trials, such as those we face in the pressures and constraints of the outer world. By the working of grace the Holy Spirit educates us in spiritual freedom in order to make us free collaborators in his work in the Church and in the world: Almighty and merciful God, in your goodness take away from us all that is harmful, so that, made ready both in mind and body, we may freely accomplish your will. [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.] [2002, 1784]
1743 "God willed that man should be left in the hand of his own counsel (cf. Sir 15:14), so that he might of his own accord seek his creator and freely attain his full and blessed perfection by cleaving to him" (GS 17 § 1).
1744 Freedom is the power to act or not to act, and so to perform deliberate acts of one's own. Freedom attains perfection in its acts when directed toward God, the sovereign Good.
1745 Freedom characterizes properly human acts. It makes the human being responsible for acts of which he is the voluntary agent. His deliberate acts properly belong to him.
1746 The imputability or responsibility for an action can be diminished or nullified by ignorance, duress, fear, and other psychological or social factors.
1747 The right to the exercise of freedom, especially in religious and moral matters, is an inalienable requirement of the dignity of man. But the exercise of freedom does not entail the putative right to say or do anything.
1748 "For freedom Christ has set us free" (Gal 5:1).
THE MORALITY OF HUMAN ACTS
1749 Freedom makes man a moral subject. When he acts deliberately, man is, so to speak, the father of his acts. Human acts, that is, acts that are freely chosen in consequence of a judgment of conscience, can be morally evaluated. They are either good or evil. 
I. THE SOURCES OF MORALITY
1750 The morality of human acts depends on:
- the object chosen;
- the end in view or the intention;
- the circumstances of the action.
The object, the intention, and the circumstances make up the "sources," or constitutive elements, of the morality of human acts.
1751 The object chosen is a good toward which the will deliberately directs itself. It is the matter of a human act. The object chosen morally specifies the act of the will, insofar as reason recognizes and judges it to be or not to be in conformity with the true good. Objective norms of morality express the rational order of good and evil, attested to by conscience. 
1752 In contrast to the object, the intention resides in the acting subject. Because it lies at the voluntary source of an action and determines it by its end, intention is an element essential to the moral evaluation of an action. The end is the first goal of the intention and indicates the purpose pursued in the action. The intention is a movement of the will toward the end: it is concerned with the goal of the activity. It aims at the good anticipated from the action undertaken. Intention is not limited to directing individual actions, but can guide several actions toward one and the same purpose; it can orient one's whole life toward its ultimate end. For example, a service done with the end of helping one's neighbor can at the same time be inspired by the love of God as the ultimate end of all our actions. One and the same action can also be inspired by several intentions, such as performing a service in order to obtain a favor or to boast about it. [2520, 1731]
1753 A good intention (for example, that of helping one's neighbor) does not make behavior that is intrinsically disordered, such as lying and calumny, good or just. The end does not justify the means. Thus the condemnation of an innocent person cannot be justified as a legitimate means of saving the nation. On the other hand, an added bad intention (such as vainglory) makes an act evil that, in and of itself, can be good (such as almsgiving). [Cf. Mt 6:24] [2479, 596]
1754 The circumstances, including the consequences, are secondary elements of a moral act. They contribute to increasing or diminishing the moral goodness or evil of human acts (for example, the amount of a theft). They can also diminish or increase the agent's responsibility (such as acting out of a fear of death). Circumstances of themselves cannot change the moral quality of acts themselves; they can make neither good nor right an action that is in itself evil. 
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, indzependently 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. 
1757 The object, the intention, and the circumstances make up the three "sources" of the morality of human acts.
1758 The object chosen morally specifies the act of willing accordingly as reason recognizes and judges it good or evil.
1759 "An evil action cannot be justified by reference to a good intention" (cf. St. Thomas Aquinas, Dec. praec. 6). The end does not justify the means.
1760 A morally good act requires the goodness of its object, of its end, and of its circumstances together.
1761 There are concrete acts that it is always wrong to choose, because their choice entails a disorder of the will, i.e., a moral evil. One may not do evil so that good may result from it.
THE MORALITY OF THE PASSIONS
1762 The human person is ordered to beatitude by his deliberate acts: the passions or feelings he experiences can dispose him to it and contribute to it.
1763 The term "passions" belongs to the Christian patrimony. Feelings or passions are emotions or movements of the sensitive appetite that incline us to act or not to act in regard to something felt or imagined to be good or evil.
1764 The passions are natural components of the human psyche; they form the passageway and ensure the connection between the life of the senses and the life of the mind. Our Lord called man's heart the source from which the passions spring. [Cf. Mk 7:21] 
1765 There are many passions. The most fundamental passion is love, aroused by the attraction of the good. Love causes a desire for the absent good and the hope of obtaining it; this movement finds completion in the pleasure and joy of the good possessed. The apprehension of evil causes hatred, aversion, and fear of the impending evil; this movement ends in sadness at some present evil, or in the anger that resists it.
1766 "To love is to will the good of another." [St. Thomas Aquinas, STh I-II, 26, 4, corp. art] All other affections have their source in this first movement of the human heart toward the good. Only the good can be loved. [Cf. St. Augustine, De Trin., 8, 3, 4: PL 42, 949-950] Passions "are evil if love is evil and good if it is good." [St. Augustine, De civ. Dei 14, 7, 2: PL 41, 410] 
II. PASSIONS AND MORAL LIFE
1767 In themselves passions are neither good nor evil. They are morally qualified only to the extent that they effectively engage reason and will. Passions are said to be voluntary, "either because they are commanded by the will or because the will does not place obstacles in their way." [St. Thomas Aquinas, STh I-II, 24, 1 corp. art] It belongs to the perfection of the moral or human good that the passions be governed by reason. [Cf. St. Thomas Aquinas, STh I-II, 24, 3] 
1768 Strong feelings are not decisive for the morality or the holiness of persons; they are simply the inexhaustible reservoir of images and affections in which the moral life is expressed. Passions are morally good when they contribute to a good action, evil in the opposite case. The upright will orders the movements of the senses it appropriates to the good and to beatitude; an evil will succumbs to disordered passions and exacerbates them. Emotions and feelings can be taken up into the virtues or perverted by the vices. [1803, 1865]
1769 In the Christian life, the Holy Spirit himself accomplishes his work by mobilizing the whole being, with all its sorrows, fears and sadness, as is visible in the Lord's agony and passion. In Christ human feelings are able to reach their consummation in charity and divine beatitude.
1770 Moral perfection consists in man's being moved to the good not by his will alone, but also by his sensitive appetite, as in the words of the psalm: "My heart and flesh sing for joy to the living God." [Ps 84:2] 
1771 The term "passions" refers to the affections or the feelings. By his emotions man intuits the good and suspects evil.
1772 The principal passions are love and hatred, desire and fear, joy, sadness, and anger.
1773 In the passions, as movements of the sensitive appetite, there is neither moral good nor evil. But insofar as they engage reason and will, there is moral good or evil in them.
1774 Emotions and feelings can be taken up in the virtues or perverted by the vices.
1775 The perfection of the moral good consists in man's being moved to the good not only by his will but also by his "heart."
1776 "Deep within his conscience man discovers a law which he has not laid upon himself but which he must obey. Its voice, ever calling him to love and to do what is good and to avoid evil, sounds in his heart at the right moment.... For man has in his heart a law inscribed by God.... His conscience is man's most secret core and his sanctuary. There he is alone with God whose voice echoes in his depths." [GS 16] 
I. THE JUDGMENT OF CONSCIENCE
1777 Moral conscience, [Cf. Rom 2:14-16] present at the heart of the person, enjoins him at the appropriate moment to do good and to avoid evil. It also judges particular choices, approving those that are good and denouncing those that are evil. [Cf. Rom 1:32] It bears witness to the authority of truth in reference to the supreme Good to which the human person is drawn, and it welcomes the commandments. When he listens to his conscience, the prudent man can hear God speaking. [1766, 2071]
1778 Conscience is a judgment of reason whereby the human person recognizes the moral quality of a concrete act that he is going to perform, is in the process of performing, or has already completed. In all he says and does, man is obliged to follow faithfully what he knows to be just and right. It is by the judgment of his conscience that man perceives and recognizes the prescriptions of the divine law: 
Conscience is a law of the mind; yet [Christians] would not grant that it is nothing more; I mean that it was not a dictate, nor conveyed the notion of responsibility, of duty, of a threat and a promise.... [Conscience] is a messenger of him, who, both in nature and in grace, speaks to us behind a veil, and teaches and rules us by his representatives. Conscience is the aboriginal Vicar of Christ. [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]
1779 It is important for every person to be sufficiently present to himself in order to hear and follow the voice of his conscience. This requirement of interiority is all the more necessary as life often distracts us from any reflection, self-examination or introspection: 
Return to your conscience, question it.... Turn inward, brethren, and in everything you do, see God as your witness. [St. Augustine, In ep Jo. 8, 9: PL 35, 2041]
1780 The dignity of the human person implies and requires uprightness of moral conscience. Conscience includes the perception of the principles of morality (synderesis); their application in the given circumstances by practical discernment of reasons and goods; and finally judgment about concrete acts yet to be performed or already performed. The truth about the moral good, stated in the law of reason, is recognized practically and concretely by the prudent judgment of conscience. We call that man prudent who chooses in conformity with this judgment. 
1781 Conscience enables one to assume responsibility for the acts performed. If man commits evil, the just judgment of conscience can remain within him as the witness to the universal truth of the good, at the same time as the evil of his particular choice. The verdict of the judgment of conscience remains a pledge of hope and mercy. In attesting to the fault committed, it calls to mind the forgiveness that must be asked, the good that must still be practiced, and the virtue that must be constantly cultivated with the grace of God: 
We shall... reassure our hearts before him whenever our hearts condemn us; for God is greater than our hearts, and he knows everything. [1 Jn 3:19-20]
1782 Man has the right to act in conscience and in freedom so as personally to make moral decisions. "He must not be forced to act contrary to his conscience. Nor must he be prevented from acting according to his conscience, especially in religious matters." [DH 3 § 2] 
II. THE FORMATION OF CONSCIENCE
1783 Conscience must be informed and moral judgment enlightened. A well-formed conscience is upright and truthful. It formulates its judgments according to reason, in conformity with the true good willed by the wisdom of the Creator. The education of conscience is indispensable for human beings who are subjected to negative influences and tempted by sin to prefer their own judgment and to reject authoritative teachings. 
1784 The education of the conscience is a lifelong task. From the earliest years, it awakens the child to the knowledge and practice of the interior law recognized by conscience. Prudent education teaches virtue; it prevents or cures fear, selfishness and pride, resentment arising from guilt, and feelings of complacency, born of human weakness and faults. The education of the conscience guarantees freedom and engenders peace of heart. 
1785 In the formation of conscience the Word of God is the light for our path, [Cf. Ps 119:105] we must assimilate it in faith and prayer and put it into practice. We must also examine our conscience before the Lord's Cross. We are assisted by the gifts of the Holy Spirit, aided by the witness or advice of others and guided by the authoritative teaching of the Church. [Cf. DH 14] 
III. TO CHOOSE IN ACCORD WITH CONSCIENCE
1786 Faced with a moral choice, conscience can make either a right judgment in accordance with reason and the divine law or, on the contrary, an erroneous judgment that departs from them.
1787 Man is sometimes confronted by situations that make moral judgments less assured and decision difficult. But he must always seriously seek what is right and good and discern the will of God expressed in divine law. 
1788 To this purpose, man strives to interpret the data of experience and the signs of the times assisted by the virtue of prudence, by the advice of competent people, and by the help of the Holy Spirit and his gifts. 
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." [Mt 7:12; cf. Lk 6:31; Tob 4:15] 
- 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." [1 Cor 8:12] Therefore "it is right not to... do anything that makes your brother stumble." [Rom 14:21] [1827, 1971]
IV. ERRONEOUS JUDGMENT
1790 A human being must always obey the certain judgment of his conscience. If he were deliberately to act against it, he would condemn himself. Yet it can happen that moral conscience remains in ignorance and makes erroneous judgments about acts to be performed or already committed.
1791 This ignorance can often be imputed to personal responsibility. This is the case when a man "takes little trouble to find out what is true and good, or when conscience is by degrees almost blinded through the habit of committing sin." [GS 16] In such cases, the person is culpable for the evil he commits. 
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. 
1793 If - on the contrary - the ignorance is invincible, or the moral subject is not responsible for his erroneous judgment, the evil committed by the person cannot be imputed to him. It remains no less an evil, a privation, a disorder. One must therefore work to correct the errors of moral conscience. 
1794 A good and pure conscience is enlightened by true faith, for charity proceeds at the same time "from a pure heart and a good conscience and sincere faith." [1 Tim 5; cf. 8:9; 2 Tim 3; 1 Pet 3:21; Acts 24:16] 
The more a correct conscience prevails, the more do persons and groups turn aside from blind choice and try to be guided by objective standards of moral conduct. [GS 16]
1795 "Conscience is man's most secret core, and his sanctuary. There he is alone with God whose voice echoes in his depths" (GS 16).
1796 Conscience is a judgment of reason by which the human person recognizes the moral quality of a concrete act.
1797 For the man who has committed evil, the verdict of his conscience remains a pledge of conversion and of hope.
1798 A well-formed conscience is upright and truthful. It formulates its judgments according to reason, in conformity with the true good willed by the wisdom of the Creator. Everyone must avail himself of the means to form his conscience.
1799 Faced with a moral choice, conscience can make either a right judgment in accordance with reason and the divine law or, on the contrary, an erroneous judgment that departs from them.
1800 A human being must always obey the certain judgment of his conscience.
1801 Conscience can remain in ignorance or make erroneous judgments. Such ignorance and errors are not always free of guilt.
1802 The Word of God is a light for our path. We must assimilate it in faith and prayer and put it into practice. This is how moral conscience is formed.