Reliance on Divine direction and acceptance of Divine grace are two essentials of true spiritual life. However, teachings such as the Christian doctrine of Original Sin emphasize reliance on grace to a possibly dangerous degree.
According to the theory of Original Sin, salvation is Gods gift of pure and undeserved mercy. There is nothing man can do to merit or earn salvation -- and it would be an act of arrogance to even try. According to other spiritual teachings, however, spiritual evolution is an active process of upleveling our vibration through purification of energy, thought, and behavior, to the point of resonance with our inherent Divine nature.
How can we reconcile these conflicting teachings? The answer is simply that they describe and address different needs, which arise at different stages of spiritual evolution corresponding to identification with different levels of ones own being. In early stages spiritual development, conscious identification is predominantly with ego. Turning ego-identified people away from a self-directed life, and toward an intimate and trusting relationship with God, has great merit. After all, ego is NOT perfectible. Thus, it makes sense that Christianity tells them, "Due to original sin, you are inherently flawed, and you are not perfectible." And, "To err is human; to forgive, Divine."
However, the human soul matures by making sincere attempts to improve itself. In that process, the limitations of egotism are confronted, understood, and transcended. At the same time, identification shifts more and more to spirit, which is already perfect. As the individuals ability to be responsible increases, the desire for FORGIVENESS is eclipsed by the desire to be HELD ACCOUNTABLE. Teachings that exhort human participation address these more spirit-identified souls, who are eager to correct their spiritual errors and who are more identified with that which is already perfect.
Christ himself addressed this aspect of mans experience when he said, "Take up the cross and follow me," and "Be perfect even as your Father in Heaven is perfect."