Based from the Catholic Encyclopedia, “Sin is nothing else than a morally bad act.” According to St. Thomas, De malo, 7:3, sin is an act not in accord with the reason informed by the Divine Law”. Sin is committed if we do not love ourselves, others and God. God gave us gifts; the theological virtues and the moral virtues. And we are blessed that God bestowed those to us in order for us to be good and to do good for the love and service of God. Though we are not perfect, yet we must try to practice exercise these virtues in order not to commit sins and evade some occasions, specifically the persons (bad companions), places (dance halls) and things (pornography). However, in spite the fact how much you would like to overcome such, yet we do commit sins, the capital sins.
There are two general classes of sins: the original sin which we inherit from Adam and the actual sin which we commit by ourselves. The actual sin has two kinds. First is the venial sin which is a less serious evil doing against the law of God. This does not deny the soul of sanctifying grace. This can be forgiven even without sacramental confession. However, if it is repeated often, this leads to commit mortal sin due to lack of self-control and weak to resist evil. Second is the mortal sin which is a terrible sin against the law of God. It is any willful thought, desire, word, action or omission in severe disobedience of God’s law. The sanctifying grace, the supernatural life of the soul is withdrawn from the sinner; thus, he is considered a living dead. Mortal sin is a greater evil than disease or poverty for it separates us from God. It makes us morally disquiet for we lose the stillness and the happiness of the just soul. Thus, we do commit the capital sins, the sins committed against the moral virtues.