In Christian views sin is an evil human act, which violates the rational nature of man as well as God's nature and his eternal law. According to the classical definition of St. Augustine of Hippo sin is "a word, deed, or desire in opposition to the eternal law of God."
The doctrine of sin is central to Christianity, since its basic message is about redemption in Christ. Christian hamartiology (from Greek, hamartia, "a departure fr. either human or divine standards of uprightness" and -, -logia, "study"), a branch of Christian theology which is the study of sin, describes sin as an act of offence against God by despising his persons and Christian biblical law, and by injuring others. Christian hamartiology is closely related to concepts of natural law, moral theology and Christian ethics.
Among some scholars, sin is understood mostly as legal infraction or contract violation of non-binding philosophical frameworks and perspectives of Christian ethics, and so salvation tends to be viewed in legal terms. Other Christian scholars understand sin to be fundamentally relational--a loss of love for the Christian God and an elevation of self-love ("concupiscence", in this sense), as was later propounded by Augustine in his debate with the Pelagians. As with the legal definition of sin, this definition also affects the understanding of Christian grace and salvation, which are thus viewed in relational terms.
The first reference to "sin" as a noun is of "sin is crouching at your door; it desires to have you, but you must rule over it" waiting to be mastered by Cain,[Gen 4:7][cf. 1 Pet 5:8] a form of literary theriomorphism. The first use of the verb is God appears to Abimelech "in the dream, "Yes, I know you did this with a clear conscience, and so I have kept you from sinning against me. That is why I did not let you touch her."" in Genesis 20:6. Isaiah announced the consequences: "But your iniquities have separated you from your God; your sins have hidden his face from you, so that he will not hear. For your hands are stained with blood, your fingers with guilt. Your lips have spoken falsely, and your tongue mutters wicked things" -- a separation between God and man, and unrequited worshipping.[Isaiah 59:2-3]
Original sin, also called ancestral sin, is the Christian doctrine of humanity's state of sin resulting from the fall of man, stemming from Adam's rebellion in Eden, namely the sin of disobedience in consuming from the tree of knowledge of good and evil. This condition has been characterized in many ways, ranging from something as insignificant as a slight deficiency, or a tendency toward sin yet without collective guilt, referred to as a "sin nature", to something as drastic as total depravity or automatic guilt of all humans through collective guilt.
The concept of original sin was first alluded to in the 2nd century by Irenaeus, Bishop of Lyon in his controversy with certain dualist Gnostics. Other church fathers such as Augustine also developed the doctrine, seeing it as based on the New Testament teaching of Paul the Apostle ( and ) and the Old Testament verse of .Tertullian, Cyprian, Ambrose and Ambrosiaster considered that humanity shares in Adam's sin, transmitted by human generation. Augustine's formulation of original sin was popular among Protestant reformers, such as Martin Luther and John Calvin, who equated original sin with concupiscence, affirming that it persisted even after baptism and completely destroyed freedom. The Jansenist movement, which the Catholic Church declared to be heretical, also maintained that original sin destroyed freedom of will.
Substantial branches of hamartiological understanding, including Roman Catholic, Presbyterian, Continental Reformed, and Reformed Baptist subscribe to the doctrine of original sin, which the Apostle Paul espouses in Romans 5:12-19 and which Augustine of Hippo popularized in the West and developed into a notion of "hereditary sin". The North African bishop taught that God holds all the descendants of Adam and Eve accountable for Adam's sin of rebellion, and as such all people deserve God's wrath and condemnation - apart from any actual sins they personally commit.
In contrast, a view sometimes ascribed to Pelagius states that humans enter life as moral "blank slates" (tabulae rasae) responsible for their own moral nature.The Fall that occurred when Adam and Eve disobeyed God, according to Pelagianism, affected humankind only minimally as it established a negative moral precedent. Few contemporary theologians (especially thinkers in Augustinian traditions) and no orthodox theologians, however, continue to hold this hamartiological viewpoint.
A third branch of thinking takes an intermediate position, asserting that since the Fall the sin of Adam has naturally affected human beings such that they have inborn tendencies to rebel against God (in which rebellion by personal choice all accountable humans, except Jesus and, to Catholics, Mary, will choose or have chosen to indulge). This is the hamartiological position of the Eastern Christian churches, often called ancestral sin as opposed to original sin, but it is sometimes viewed as Semipelagian in the West, especially by the Reformed.
Sin can be divided by reason of:
The way Thomas Aquinas viewed sin and vices was radically different from later approaches, especially that of 17th-century moral theology. He presented sin and vices as contraries of virtues. He discusses the subject in his Summa Theologica part Ia-IIae (Prima secundae) qq. 71-89.
Now there are two rules of the human will: one is proximate and homogeneous, viz. the human reason; the other is the first rule, viz. the eternal law, which is God's reason, so to speak (quasi ratio Dei). Accordingly Augustine includes two things in the definition of sin; one, pertaining to the substance of a human act, and which is the matter, so to speak, of sin, when he says, word, deed, or desire; the other, pertaining to the nature of evil, and which is the form, as it were, of sin, when he says, contrary to the eternal law. (STh I-II q.71 a.6)
To recognise the possibilities of sin in man is equal to acknowledge his human nature, his control and mastery of his own actions. Sin is a motion to the goal, it is judged by the object to which it is directed. The field of sin is the same as the field of virtue. There are three major fields: relationship with God, with oneself and with the neighbour. Thomas distinguished between mortal and venial sins. Mortal sin is when a person has irreparably destroyed the very principle of his/her order to the goal of life. Venial sin is when he/she has acted in a certain disordered way without destructing that principle:
Consequently it is a mortal sin generically, whether it be contrary to the love of God, e.g. blasphemy, perjury, and the like, or against the love of one's neighbour, e.g. murder, adultery, and such like: wherefore such sins are mortal by reason of their genus. Sometimes, however, the sinner's will is directed to a thing containing a certain inordinateness, but which is not contrary to the love of God and one's neighbour, e.g. an idle word, excessive laughter, and so forth: and such sins are venial by reason of their genus. (STh I-II q.72 a.5)
According to Aquinas the gravity of sin depends also on some disposition of the agent (cf. STh I-II q. 18, aa. 4, 6). Sin, venial by reason of its object, may become mortal. It happens when person fixes his/her ultimate happiness, the last end of his/her life (Lat. finis ultimus) in the object of that venial sin. When venial sin is used as a way to provoke mortal sin it becomes mortal as well, e.g. when someone uses empty conversation or a chat to seduce someone to commit adultery. Also sin, mortal by reason of its object, may become venial because of the agent's disposition when his/her evil act does not have full moral capacity, i.e. is not deliberated by reason. That may happen for instance when sudden movements of unbelief arise in the mind. (Cf. STh I-II q.72 a.5).
The difference and gravity of sins may be discerned on the grounds of spirit and flesh, even mortal sins may differ in gravity. Carnal sins like lust, adultery or fornication, gluttony and avarice, because the person who commits them is inordinately directed towards material goods that are a serious matter, are mortal sins. They may cause much shame and infamy. But spiritual sins like blaspheming of God or apostasy are, according to Thomas, still greater evil, as they have more of the aversion from God. They are directed against a greater object. The formal, essential element of sin is more at the centre in them. (cf. STh I-II q.72 a.2)
According to another formulation of the concept of sin in the Summa, at the heart of sin is "the turning away from the immutable good", i.e. God, and "inordinate turning to mutable good", i.e. creatures. (STh I-IIae q.87 a.4) This cannot be understood as if in the concrete sinful deed the sinner commits two separate and independent acts. Both aversio and conversio constitute one single guilty action. At the root of the inordinate turning to the creatures is self-love which expresses itself in disordered desire (cupiditas) and rebellion towards God (superbia).
Speaking about sloth (Lat. acedia) Thomas points out that every deed which "by its very nature is contrary to charity is a mortal sin". An effect of such deed is the destruction of "spiritual life which is the effect of charity, whereby God dwells in us." Sin of a mortal character is always committed with the consent of reason: "Because the consummation of sin is in the consent of reason"'. (cf. STh II-IIae q.35 a.3) Venial and mortal sins can be compared to sickness and death. While venial sin impairs full healthy activity of a person, mortal sin destroys the principle of spiritual life in him/her.
Mortal sins are sins of grave (serious) matter, where the sinner performs the act with full knowledge and deliberate consent. (cf. CCC 1857) The act of committing a mortal sin destroys charity, i. e. the grace in the heart of a Christian; it is in itself a rejection of God (CCC1855). If left un-reconciled, mortal sins may lead to eternal separation from God, traditionally called damnation.
Venial sins are sins which do not meet the conditions for mortal sins. The act of committing a venial sin does not cut off the sinner from God's grace, as the sinner has not rejected God. However, venial sins do injure the relationship between the sinner and God, and as such, must be reconciled to God, either through the Sacrament of Reconciliation or receiving the Eucharist (after proper contrition fulfilled).
Both mortal and venial sins have a dual nature of punishment. They incur both guilt for the sin, yielding eternal punishment, and temporal punishment for the sin. Reconciliation is an act of God's mercy, and addresses the guilt and eternal punishment for sin. Purgatory and indulgences address the temporal punishment for sin, and exercise of God's justice.
Roman Catholic doctrine also sees sin as being twofold: Sin is, at once, any evil or immoral action which infracts God's law and the inevitable consequences, the state of being that comes about by committing the sinful action. Sin can and does alienate a person both from God and the community. Hence, the Catholic Church's insistence on reconciliation with both God and the Church itself.
The Roman Catholic view of sin has recently expanded. Monsignor Gianfranco Girotti, Regent of the Catholic Apostolic Penitentiary, has said that "known sins increasingly manifest themselves as behavior that damages society as a whole," including, for example:
Mortal sins, which are any severe and intentional actions that directly disobey God, are often confused with the seven deadly sins, which are pride, envy, wrath, sloth, greed, gluttony, and lust. They are not, however, the same. The seven deadly sins are called "deadly" because they might lead another to commit other sins. Some forms of the seven deadly sins (i.e. debilitating one's health because of their love of food) can constitute as grave matter, while others may just be venal (i.e. over-eating).
Many Protestants of a Calvinist orientation teach that, due to original sin, humanity has lost any and all capacity to move towards reconciliation with God (Romans 3:23;6:23; Ephesians 2:1-3); in fact, this inborn sin turns humans away from God and towards themselves and their own desires (Isaiah 53:6a). Thus, humans may be brought back into a relationship with God only by way of God's rescuing the sinner from his/her hopeless condition (Galatians 5:17-21; Ephesians 2:4-10) through Jesus' substitutionary atonement (Romans 5:6-8; Colossians 2:13-15; 1 Timothy 2:5-6). According to traditional Reformed theology and classical Lutheranism, Salvation is sola fide (by faith alone); sola gratia (by grace alone); and is begun and completed by God alone through Jesus (Ephesians 2:8,9). This understanding of original sin (Romans 5:12-19), is most closely associated with Calvinist doctrine (see total depravity) and Lutheranism. Calvinism allows for the relative or nominal "goodness" of humanity through God's common grace upon both those predestined to salvation and those predestined to damnation, upon the regenerate and the unregenerate.
This is in contrast to the Roman Catholic teaching that while sin has tarnished the original goodness of humanity prior to the Fall, it has not entirely extinguished that goodness, or at least the potential for goodness, allowing humans to reach towards God to share in the Redemption which Jesus Christ won for them. Some Protestants and Orthodox Christians hold similar views.
There is dispute about where sin originated. Some who interpret the king of Tyre in Ezekiel 28 as a symbol for Satan believe sin originated when Satan coveted the position that rightfully belongs to God. The origin of individual sins is discussed in James 1:14-15 - "14but each one is tempted when, by his own evil desire, he is dragged away and enticed. 15Then, after desire has conceived, it gives birth to sin; and sin, when it is full-grown, gives birth to death." (NIV)
Within some branches of Protestantism, there are several defined types of sin (as in Roman Catholicism):
The Wesleyan-Arminian theology of the Methodist Churches teaches that humans, though being born in total depravity, can turn to God as a result of prevenient grace and do good; this prevenient grace convicts humans of the necessity of the new birth (first work of grace), through which he is justified (pardoned) and regenerated. When the believer is entirely sanctified (second work of grace), his/her original sin is washed away. After this, to willfully sin would be to fall from grace.
Original sin is the sin which corrupts our nature and gives us the tendency to sin. Actual sins are the sins we commit every day before we are saved, such as lying, swearing, stealing.
It further categorizes sin as being "sin proper" and "sin improper". Sins proper (or sin, properly so called) are those that are committed freely and willfully, which result in a loss of entire sanctification. Sins improper (or sin, improperly so called) are those in the "category of benign neglect, fruits of infirmity (forgetfulness, lack of knowledge, etc)". In traditional Methodist theology, these (improper) sins are not classified as sins, as explained by Wesley, "Such transgressions you may call sins, if you please: I do not, for the reasons above-mentioned." John Wesley explains the matter like this:
"Nothing is sin, strictly speaking, but a voluntary transgression of a known law of God. Therefore, every voluntary breach of the law of love is sin; and nothing else, if we speak properly. To strain the matter farther is only to make way for Calvinism. There may be ten thousand wandering thoughts, and forgetful intervals, without any breach of love, though not without transgressing the Adamic law. But Calvinists would fain confound these together. Let love fill your heart, and it is enough!"
The (Chalcedonian) Eastern Orthodox as well as the (non-Chalcedonian) Oriental Orthodox use "sin" both to refer to humanity's fallen condition and to refer to individual sinful acts. In many ways the Orthodox Christian view of sin is similar to the Jewish, although neither form of Orthodoxy makes formal distinctions among "grades" of sins.
The Eastern Catholic Churches, which derive their theology and spirituality from same sources as the Eastern Orthodox and Oriental Orthodox, tend not to adhere to the Roman Catholic distinction between mortal and venial sin taught by the Latin Church. Like the Orthodox Churches, however, the Eastern Catholic Churches do make a distinction between sins that are serious enough to bar one from Holy Communion (and must be confessed before receiving once again) and those which are not sufficiently serious to do so. In this respect, the Eastern Tradition is similar to the Western, but the Eastern Churches do not consider death in such a state to automatically mean damnation to "hell."
Jehovah's Witnesses believe that sin is inherited, like a disease, and has been passed on from generation to generation of humans, beginning with Adam and Eve, whom Witnesses believe are real historical characters. They believe that it began with the Devil, and then with humans wanting to decide for themselves what was good and bad. They believe that at that very moment they lost perfection and began to die. Jehovah's Witnesses consider human beings to be souls, and so when a human dies due to sin, they believe that his soul dies as well. They believe that Jesus is the only human ever to have lived and died sinless.
Members of The Church of Jesus Christ of Latter-day Saints believe that individuals are only responsible for the sins they personally commit. In their Articles of Faith the Church of Jesus Christ of Latter-day Saints teaches, "We believe that men will be punished for their own sins, and not for Adam's transgression." Latter-day Saints also believe that sin is the consequence of the Fall of Adam and Eve, and that all sin originates from Satan. They also believe that "little children" (meaning those under the age of 8) are not capable of sinning, because they are not yet accountable for their actions.
In Christianity, it is generally understood that the death of Jesus was a sacrifice that relieves believers of the burden of their sins. However, the actual meaning of this precept is very widely debated. The traditional teaching of some churches traces this idea of atonement to blood sacrifices in the ancient Hebraic faith.
Christian theologians have presented different interpretations of atonement:
Q. What other sins ought we to fear most? A. The other sins that we ought to fear most are sins against the Holy Ghost and sins that cry to Heaven for vengeance.
The only way a person can "lose" ("reject" is a better term) his entire sanctification is through willful sin or unbelief (which is also sin).
Does an entirely sanctified person who rebels against God but later comes back to Him need to be entirely sanctified again? We do know that a person can rebel against God and later turn back in repentance and then be "re-saved." Answer: Yes. To come back to God is the action of a backslider having his re in need of continual cleansing. The verb "cleanses us" is a present indica-relationship with God restored. After the restoration, one must walk in the light and obey Romans 12:1 and offer himself a living, holy, and acceptable sacrifice to God. This can be done only by a person in right relationship with God.