Sins are what separate us from God and the heaven He has created for us. Sins are contrary to the law of God and can be by thought, word or by deed. There are different degrees of sin; not all are equally serious. The Church makes a distinction between sins stating that they are either venial or mortal sins. The distinction is determined according to scriptural references. You may not find the words venial and mortal in the Bible but the examples and consequences of each type of sin are plainly recorded. The Catholic Church merely applied names to the different degrees of sins as listed in the Bible
The New Testament maintains this distinction. In teaching his disciples to pray, Jesus directs them to seek forgiveness for their daily transgressions (see Mt. 6.12; Lk. 11.4). By contrast, he threatens his determined opponents with the condemnation of Gehenna (see Mt. 23.33). Certain sins exclude one from the kingdom forever (see Mt 25.43-46); some are unforgivable in a way that others are not (see Mt. 12.31-32; Mk. 3.28-30).
The Epistles reveal daily sins of which everyone can be guilty (see Jas. 3.2; 1 Jn. 1.
. Then there also is the slavery to sin which leads to death (see Rom. 6.16). Certain sins call for excommunication (see 1 Cor. 5.13). The grave sins exclude from the kingdom (see 1 Cor. 6.9-10; Gal 5.19-21). (From Christian Moral Principles, Distinction among Sins, Sins of thought -- Chapter 15)
(Q): What is a Mortal Sin?
(A): Mortal sin is a grievous offense against the law of God. It is called mortal, which means deadly, because it deprives the sinner of sanctifying grace. In addition, mortal sin makes the soul an enemy of God. It takes away the merit of all its good actions. It deprives it of the right of everlasting happiness in heaven and makes it deserving of everlasting punishment in hell. To make a sin mortal three things are necessary:
(1) the thought, desire, work, action, or omission must be seriously wrong or considered seriously wrong;
(2) The sinner must be mindful of the serious wrong;
(3) The sinner must fully consent to it (Baltimore Catechism).
A mortal sin is a sin, which is incompatible with divine life. Those who commit and remain in mortal sin are excluded from the kingdom of God; they are separated from Jesus; they evict the Holy Spirit from their hearts. They incapacitate themselves for life in the Church, particularly for the reception of Holy Communion, which expresses and nourishes the living unity of humankind redeemed in Jesus. (From Christian Moral Principles, Distinction among Sins, Sins of thought -- Chapter 15)
The conditions required for mortal sin are three: grave matter, sufficient reflection, and full consent.
(Q): What are some examples of Mortal Sins?
(A): Some acts that are mortal sins are--killing the innocent, adultery, lying, theft, and so on. Of the latter, however, some necessarily bring about great harm: In killing the innocent the victim cannot be only somewhat dead, and in adultery the marriage bond cannot be only slightly defiled. Others can sometimes involve slight harm: In stealing, one can take a newspaper without paying for it or one can take somebody's entire livelihood; in lying, one can make a harmless joke or one can practice deception in a matter of life and death. (From Christian Moral Principles, Distinction among Sins, Sins of thought -- Chapter 15)
(Q): What is a Venial Sin?
(A): Venial sin is a less serious offence against the law of God. It does not deprive the soul of sanctifying grace, and it can be pardoned even without sacramental confession. A sin is venial when the evil done is not seriously wrong. It is venial when the evil done is seriously wrong but the sinner sincerely believes it is only slilghtly wrong, or does not give full consent to it. Venial sin harms us by making us less fervent in the service of God. It weakens our power to resist mortal sin. It also makes us deserving of God's punishments in this life or in purgatory (Baltimore Catechism).
Venial sin is a slight offence against the law of God in matters of less importance; or in matters of great importance it is an offence committed with out sufficient reflection or full consent of the will. (The Baltimore Catechism)
(Q): How can we keep from committing sin?
(A): We can keep from committing sin:
(1) by praying and receiving the sacraments (See Sacraments);
(2) by remembering that God is always with us;
(3) by recalling that our bodies are temples of the Holy Ghost;
(4) by keeping occupied with work and play;
(5) by promptly resisting the sources of sin within us;
(6) by avoiding the near occasion of sin.
(Q): What are the chief sources of sin?
(A): There are seven chief sources of sin: pride, covetousness, lust, anger, gluttony, envy, and sloth.
(NOTE: the following is taken from the Saint Meinrad Prayer Book)
PRIDE: Those who are prideful have a great admiration for their self. Prideful individuals make their own laws, and are judges of morality and are in essence their own God. Pride produces criticism, back-biting, slander, and character assassination, all of which elevates the ego of a prideful person
Pride produces:
Boasting - self glorification
Love of publicity - conceit in what others say
Hypocrisy-pretending to be what they are not
Discord-resenting anyone who crosses them
Quarrelsomeness--quarreling whenever another challenges their wishes
Disobedience--refusal to submit my will to the will of lawful superiors and to God's will.
COVETOUSNESS OR AVARICE: A perversion of humankind's God-given right to own things. Do I desire wealth in the form of money or other things as an end to itself rather than as a means to an end? In acquiring any type of wealth, do I disregard the rights of others? Am I dishonest, and if so, to what degree and in what fashion? How do I use what I have? Do I stoop to such devices as fraud, perjury or dishonesty in dealing with others? Do I fool myself by calling these practices by some other name than what they truly are?
LUST: an inordinate love and desire of the pleasures of the flesh. Do I engage in any type of sexual activity outside of marriage? If married, do I treat my spouse with respect or as a possession? Do I really think lust is love or that sex is love? Is my sense of values harmed by my lack of prudence and rashness?
ENVY: - Sadness at another's success. Does someone else's good fortune mean I am less of a person? Does their happiness or success take away from who I am or what I have accomplished? Do I resent those who are smarter, more socially adept, or more savvy than I? Do I criticize the good done by other because I secretly wish that I'd done it myself for the honor or prestige to be gained?
ANGER: - A violent desire to punish others. Do I ever fly into rages of temper, become revengeful, entertain urges to "get even with" someone? Do I ever resort to violence, clench fists or stomp about in a rage? Am I touchy, unduly sensitive, impatient in the least? Do I let anger disrupt my mental poise and good judgment? Do I permit myself to become angry when others are weak and become angry with me?
GLUTTONY: An abuse of lawful pleasures God attached to eating and drinking foods required for self-preservation. Do I ever drink alcohol to a level in which my intellect and personality deteriorate; my memory, judgment and concentration are affected; my personal pride and social judgment vanish; that I developed a spirit of despair?
SLOTH: An illness of the will that causes a neglect of duty. Am I lazy, given to idleness, procrastination, nonchalance, and indifference in material things? Am I lukewarm in my prayer life? Am I easily distracted from things spiritual, quickly turning to things temporal? Am I ever indolent to the extent that I perform work carelessly?