Remember that you are not saved by increased levels of holiness, however desirable it is that you should reach them. Indeed, while we often say that we are “saved by faith” or by “faith in Christ,” as Benjamin B. Warfield shrewdly comments, it is not even faith in Christ that saves us. It is Christ who saves us—through faith.
Your faith is a poor and crumbling thing, as is your spiritual service. Jesus Christ alone is qualified and able to save you because of what He has done. Cling to anything else and you are relying on flotsam and jetsam floating on a perilous sea. It will bring you down under the waves. If you should ever experience anything like the satanic attack Bunyan’s Christian endured, you will be lost. But cling to Christ Jesus and His righteousness, and nothing can sink you.
When you grasp that, you begin to realize why and how it is that you can live in the face of such demonic attacks as these [accusation]. You are not pushed back on your own resources or spiritual qualities. You are able to rest exclusively on what Jesus Christ has done for you. For what He has done for you is absolutely perfect.
What Christ is doing in you is still incomplete. But in what Jesus Christ has done for you there is not a single tiny crack that the satanic arrows can penetrate. Jesus Christ is your shield. You can say, with David, “The Lord is . . . my deliverer; my God . . . in whom I will trust; my shield and the horn of my salvation, my stronghold. I will call upon the Lord, who is worthy to be praised; so shall I be saved from my enemies” (Ps. 18:2–3)…
Here is our refuge: In Christ, we are as righteous before God as Jesus Christ is righteous, for the only righteousness we have before God is Jesus Christ’s righteousness, to which we contribute nothing.
Faith contributes nothing to that righteousness. The years we may have lived the Christian life contribute nothing to that righteousness. Conversely, our sins cannot diminish that righteousness.
Is that not a dangerous thing to say? It would be if it were distorted. But the truth is that no other kind of righteousness can justify us.
But because this is the righteousness by which we are justified, Paul can say: “Who shall bring any charge against God’s elect?” (v. 33).
Sinclair Ferguson, By Grace Alone: How the Grace of God Amazes Me, pp. 75-76