Those who approach the sacrament of Penance obtain pardon from the mercy of God for the offence committed against Him and are at the same time reconciled with the Church, which they have wounded by their sins, and which by charity, example, and prayer seeks their conversion. (Conc.Vat. II, LG 11)
Christ trusts the exercise of the power of absolution of sins to the apostolic ministry. To those is entrusted the ministry of reconciliation (2Cor 5:18). The apostle is send in the Name of Christ and it is God himself that through minister exhorts and asks Allow yourselves to be reconciled with God. (2Cor 5:20)
Sayings for a Good Confession.
1 – In order to confess well it is necessary to prepare oneself with prayer. Then, make an attentive examination of conscience from your last confession that you made well. This means confront yourself with the word of God to distinguish misunderstandings, weaknesses and errors in thoughts, words, acts and omissions before the teachings of the Gospels
2 – Feeling sorrow and aversion for the sins you committed with the decision of committing the same errors no more.
3 – Confess to the priest, “ambassador of God” all your grave or mortal sins according to type and number; it is very useful to frequently confess the venial sins because you receive the gift of grace that strengthens you on the road of imitating Christ.
4 – Do all possible to repair the bad. Absolution takes away sins, but does not correct all the disorder that sin causes. Therefore, forgiven from sin, the sinner should still recuperate the fullness of spiritual health. The exercise of penance that the confessor gives is not given only for the expiation of sins committed and to repair the damage caused, but also as an assistance to initiate a new life full of reparation from the sickness of sin.
This reparation is an expression of the authentic revision of life, in which the penitent obtains the support and reparation from the bad effects of his/her actions or omissions in following of Christ and in solidarity with his brothers and sisters above all and with those directly touched through his/her sins.
This can consist of prayers, mortifications and in works of mercy.
from a post by Adailton Silva (translated by Fr. Robert J. Carr)