Sinclair Ferguson maintains that while Christians sing "Amazing Grace," we have largely ceased being amazed by it. In By Grace Alone: How the Grace of God Amazes Me, he offers an antidote to our general unamazement.
To illustrate the truth that none of us truly understands -- is amazed by -- grace until we understand our need for it, Ferguson offers a helpful explanation and application of the parable of the Prodigal Son.
A significant contribution is Ferguson's assessment of the security that grace affords the believer. In discussing Romans 8:31-35 ('who can bring a charge against God's elect', etc), Ferguson challenges the Christian not to look at the circumstances of life, or how much we might 'deserve' grace, and draw conclusions about our security and God's care from them. Instead, it is in grace -- Christ's substitutionary death on the cross -- that provides security regarding our standing before God.
Ferguson also suggests that one of Satan's 'fiery darts' with which he attacks Christian was employed in his attack on Job: attempting to have Job question the good character of God and attribute to Him the devil's machinations. In other words, trying to get Job to 'exchange the truth of God for a lie.' This is, after all, how Satan tempted Eve in the Garden.
As Christ-followers, we need to constantly preach the Gospel to ourselves.
"Sometimes we imagine that our greatest need is to move on to the 'higher' or 'deeper teaching of the gospel. But in fact, our real need is to get a deeper and firmer grasp of the main truths of the gospel." (Ferguson, By Grace Alone, 102).