We all have need to repent. Sometimes we sin because of ignorance, sometimes because of our weaknesses, and sometimes because of willful disobedience. Except for Jesus Christ, who lived a perfect life, everyone who has lived upon the earth has sinned. Our Heavenly Father in his great love has provided us this opportunity to repent of our sins. Repentance is the way provided for us to become free from our sins and receive forgiveness for them.
Sins slow our spiritual progression and can even stop it.
Repentance makes it possible for us to grow and develop spiritually again. The privilege of repenting is made possible through the atonement of Jesus Christ. In a way we do not fully understand, Jesus paid for our sins. It was something terrible, something terrific. . . . Repentance sometimes requires great courage, much strength, many tears, unceasing prayers, and untiring efforts to live the commandments of the Lord.