"Godly sorrow produces repentance leading to salvation..."(2 Corinthians 7:10)
Conviction of sin is best described in the words:
My sins, my sins, my Savior,
How sad on Thee they fall.
Conviction of sin is one of the most uncommon things that ever happens to a person. It is the beginning of an understanding of God. Jesus Christ said that when the Holy Spirit came He would convict people of sin (see John 16:8). And when the Holy Spirit stirs a person's conscience and brings him into the presence of God, it is not that person's relationship with others that bothers him but his relationship with God - "Against You, You only, have I sinned, and done this evil in your sight..."(Psalm 51:4). The wonders of conviction of sin, forgiveness, and holiness are so interwoven that it is only the forgiven person who is truly holy. He proves he is forgiven by being the opposite of what he was previously, by the grace of God. Repentance always brings a person to the point of saying, "I have sinned." The surest sign that God is at work in his life is when he says that and means it. Anything less is simply sorrow for having made foolish mistakes - a reflex action caused by self- disgust.
The entrance into the kingdom of God is through the sharp, sudden pains of repentance colliding with man's respectable "goodness." Then the Holy Spirit, who produces these struggles, begins the formation of the Son of God in the person's life (see Galatians 4:19). This new life will reveal itself in conscious repentance followed by unconscious holiness, never the other way around. The foundation of Christianity is repentance. Strictly speaking, a person cannot repent when he chooses - repentance is a gift of God. The old Puritans used to pray for "the gift of tears." If you ever cease to understand the value of repentance, you allow yourself to remain in sin. Examine yourself to see if you have forgotten how to be truly repentant.