We then, as workers together with Him also plead with you not to receive the grace of God in vain. For He says: “In an acceptable time I have heard you, And in the day of salvation I have helped you.” Behold, now is the accepted time; behold, now is the day of salvation.
For the kind of sorrow God wants us to experience leads us away from sin and results in salvation. There is no regret for that kind of sorrow. But worldly sorrow, which lacks repentance, results in spiritual death.