Perfect sorrow or contrition for mortal sin restores a person to the state of grace even prior to receiving the Sacrament of Penance, providing he is sincerely sorry for offending God and intends to go to confession as soon as possible.
We have perfect sorrow for our sins when we are truly sorry for them because they have offended our loving Father in Heaven, when we hate the sins committed, and when we have a firm intention not to commit them again. Our primary motivation is contrition for having offended our God, Who is infinitely good, and not merely for fear of divine punishment. Our sorrow is sincere when it comes from the heart.
The virtue of perfect contrition is based on our love for God and the realization of His goodness. This realization should grow each time we say an act of contrition or go to confession.
Mortal sin is the greatest of all evils: it offends God seriously, keeps us out of Heaven, and condemns us forever to Hell. By perfect contrition we can be restored to grace, but the obligation to confess mortal sins to a priest remains.
The remedy for sin is Jesus Christ, Who came into the world to save His people from their sins. By sharing in Jesus’ death and Resurrection through the sacraments and by faithfully performing the duties of our state in life, we can triumph over sin and death. St. Paul says, “Christ died for us. Since, therefore, we are now justified by his blood, much more shall we be saved by him from the wrath of God” (Romans 5:8–9).