It is good to reflect often on the Sacrament of God’s mercy, Penance or Reconciliation. In Confession a person looks squarely at the sins he or she is guilty of, takes responsibility for them and opens oneself up again to God and to the communion of the Church. All mortal sins committed since one’s last worthy confession, even the most secret ones of thought and desire, must be confessed to a priest; for it is to him that our Lord has given the power to absolve from sins. Anyone, who is aware of having committed a mortal sin, must not receive Holy Communion, even if he experiences deep contrition, without having first received sacramental absolution.
To make a good confession, the penitent must:
1. Make a good examination of conscience
2. Tell all mortal sins committed since his/her last worthy confession
3. Be sorry for one’s sins with a purpose of amendment
4. Accept the penance which the confessor assigns
Besides doing the penance, it is still necessary to make reparation for sins. Justice requires this. Absolution takes away sins, but it does not remedy the disorders caused by sins, such as weakening the sinner and his relationship with God and with his neighbor. We can make reparation by prayers, almsgiving and/or works of charity. Also, justice demands that we repair the harm caused specifically by sins against our neighbor. For example, if one has stolen, he must return the stolen goods; if he has lied about someone, he must restore the reputation of the person injured; etc. For penance the priest does not usually tell the penitent to return stolen goods, etc. because it is required regardless by justice and sorrow. The penance given in confession is meant to help strengthen the penitent spiritually.
Although it is not strictly necessary to confess venial sins, it is strongly recommended by the Church. Frequent confession of our venial sins helps us form our conscience, fight against evil tendencies, let ourselves be healed by Christ and make real spiritual progress.