Nothing happens in our lives (including repentance) until God initiates it. A change of heart, by God's Holy Spirit, results in a total change of direction.
Worldly sorrow is superficial and unproductive, while godly sorrow yields not only repentance, but also a bumper crop of the fruits of God's Holy Spirit.
The contrite or brokenhearted person finds special favor with God, and a humble or contrite spirit is indeed a precursor to forgiveness and spiritual healing.
Personified Jerusalem, whom God depicts as a grieving widow, blames others for her troubles while overlooking her own sins as the real cause of her sorrow.
We must be very careful how we examine ourselves. Taking the Passover in an unworthy manner can result in serious physical or spiritual hazards.