...difficult for many to understand...

"All that God does in redeeming, reconciling and justifying man, and in giving him a new life, is of God alone. Man can contribute nothing. It is very difficult for many to understand the truth that salvation from the penalty of sin is the work of God and Him alone, and it is only our faith in Jesus Christ that makes God's work effective. But even though it is very difficult for many to understand grace in salvation, it seems even more difficult for those who are saved to understand that the life that God expects them to live is not of themselves, but by His power, which is also by His grace"