As a result of Original Sin, human nature is weakened. Baptism, by imparting the life of Christ's grace, takes away Original Sin, and turns us back toward God. When the consequences of this weakness and the inclination to evil persist, we often commit either mortal or venial sins.
Mortal sin is a deadly offense against God, so horrible that it destroys the life of grace in the soul. Three simultaneous conditions must be fulfilled for a mortal sin: 1) the act must be something very serious; 2) the person must have sufficient understanding of what is being done; 3) the person must have sufficient freedom of the will.
Venial sins are still serious but not nearly as severe as mortal sins.
(more on this in FAQs)
The essential act of Penance, on the part of the penitent, is contrition, a clear and decisive rejection of the sin committed, together with a resolution not to commit it again, out of the love one has for God and which is reborn with repentance. The resolution to avoid committing these sins in the future (amendment) is a sure sign that your sorrow is genuine and authentic. This does not mean that a promise never to fall again into sin is necessary. A resolution to try to avoid the near occasions of sin suffices for true repentance. God's grace in cooperation with the intention to rectify your life will give you the strength to resist and overcome temptation in the future.
Examination of Conscience
Before going to Confession you should make a review of mortal and venial sins since your last sacramental confession, and should express sorrow for sins, hatred for sins and a firm resolution not to sin again.
A helpful pattern for examination of conscience is to review the Commandments of God and the Precepts of the Church: (basically go through the 10 Commandments)
**Note: it is best to be as specific with your sins as possible.
The Seven Deadly Sins
PRIDE is when we seek to take credit ourselves for things that God has done. It is when we seek to bring praise and honor upon ourselves because of some ability or accomplishment rather than seeking to give praise and honor to God who accomplished these things through us.
ENVY is when we have contempt for the well being of someone else because it takes away our own glory. It’s not just wishing that you had something that someone else had, it wishing that you had it and that they didn’t have it. It is really the sin of failing to rejoice in the well being of others.
SLOTH is the sin of laziness, primarily spiritual laziness in our relationship with God. It is when we fail to seek the spiritual growth that God calls us to.
LUST is having a disordered desire for physical pleasures or for material possessions. It is called disordered because it is excessive love for something that we either should not love or something that we should not love as much as we do. Most often, but not always, this takes the form of sexual lust, where someone uses another person as a means of sexual gratification only rather than treating them with the respect and dignity that they deserve as a child of God. To USE another person is always apposed to our call to holiness.
GREED (also called avarice) is the excessive desire for material wealth or worldly honor. It seeks to gain the temporary things of this world as the means of our own value rather than seeking to please God first and foremost.
GLUTTONY (also called intemperance) is lack of self-control which leads to excessively eating, drinking, sleeping, etc. The Virtue of Temperance (the opposite of intemperance) is having a proper balance of moderation in what we do and how we live. The Sin of Gluttony (intemperance) is having an improper balance in our lives.
ANGER (also called wrath) is the sin of excessively wanting to restrain anything that poses a threat. It is when our first response is to respond violently to something that causes us a bit of discomfort. If the thing is truly something evil, then anger can be considered righteous, as long as it is exercised prudently and moderately (check out Jesus cleansing the Tempe in Jerusalem – Mark 11:15-19).
After examining your conscience and telling God of your sorrow, go into the confessional. You may kneel at the screen or sit to talk face-to-face with the priest.
Begin your confession with the sign of the cross, "In the name of the Father, and of the Son, and of the Holy Spirit. My last confession was _________ weeks (months, years) ago."
The priest may read a passage from holy Scripture.
Say the sins that you remember. Start with the one(s) that is most difficult to say. (In order to make a good confession the faithful must confess all mortal sins, according to kind and number.) After confessing all the sins you remember since your last good confession, you may conclude by saying, "I am sorry for these and all the sins of my past life."
Listen to the words of the priest. He will assign you some penance. Doing the penance will diminish the temporal punishment due to sins already forgiven. When invited, express some prayer of sorrow or Act of Contrition such as:
An Act of Contrition
O my God, I am sorry for my sins, in choosing to do wrong and failing to do good. I firmly intend with the help of your son to make up for my sins and to love you as I should. I firmly resolve with the help of your grace, to confess my sins, to do penance and to amend my life. Amen.
Give thanks to God for forgiving you again. If you recall some serious sin you forgot to tell, rest assured that it has been forgiven with the others, but be sure to confess it in your next Confession. Do you assigned Penance and try to go to confession often. We're lucky to have this Sacrament as a way to help get rid of our weakenesses and grow in faith.
"Confession is free therapy"