Dr. R. C. Sproul, Jr. writes:
The Reformation was born out of the biblical conviction that a man is deemed just in the sight of God, forgiven, adopted, not on the basis of his own goodness, but on the basis of the goodness of Christ imputed to him. Not everyone, however, is blessed with this imputation, but only those who trust in that provision, and in that provision alone. The debate at that time, and to this day, has been characterized as faith versus works. Though Rome would not affirm, and indeed rightly condemns crass Pelagianism, the notion that we can earn God’s favor outside His grace, she does see a vital role for our personal righteousness, even while affirming that our righteousness is the result of grace at work in us, with which we must cooperate. In framing the debate as works versus faith, however, some miss the very nature of faith.
One way to err on faith is in fact to turn it into a “work.” In this error we see “faith” as a substitute for our obedience. This view suggests that in the Garden God required total and complete obedience from us in order for us to be at peace with Him. When that failed, God graciously lowered His standard. Now all that He requires of us is that we trust in Him. The trouble with this view is that it wrongly makes faith the ground of our salvation. We stand before the throne of God and He asks why He should allow us into His kingdom. We boldly reply, “Because of my faith.” God then answers, “Faith? I love faith! People with faith, that’s just the kind of people I want to have around. By all means, come on in.” This error in the end is faith in faith, which faith will surely not save. It makes the cross gratuitous, which is blasphemy.
A second error turns faith into a work, and therefore rejects it as vital to our salvation. This view rightly recognizes that it is ultimately the finished work of Christ alone that saves. It rightly affirms that a man is justified because his sins were punished at Calvary, and the obedience of Christ is his. This view rightly affirms solus Christus, by Christ alone. In order, however, to fence off the first error, to be certain we don’t look at our faith as meritorious, it denudes faith of its true nature, turning it into bare assent. This view defines saving faith as agreeing to the truthfulness of the gospel message. This error suffers from two key problems. First, in diminishing the nature of saving faith to bare assent it leaves room even for, in principle, the demons. James says even the demons believe, and shudder (2:19). That is, they know God exists, and hate what they know. It is possible to know something and hate what you know. You can know, you can believe, as the devil himself knows and believes, that Jesus died for sinners, and still not have faith.
The second error here is that it doesn’t solve the problem. If we want to denude faith to be certain it doesn’t turn into a work, how does assent not become a work? Just as with true saving faith I am the one believing, trusting, resting, so even if it is mere assent I am the one assenting. In short, if faith is a work, why isn’t assent a work?
We avoid both problems when we embrace the wisdom of our fathers, the Westminster Divines. In their Shorter Catechism they ask, “What is faith in Jesus Christ?” and answer, “Faith in Jesus Christ is a saving grace, whereby we receive and rest upon Him alone for salvation as He is offered to us in the gospel” (question 86). Faith is not a work on two counts. First, it is a gift from God. It is not just received by grace, but is a grace. Faith is something God gives to us. On our own it is not possible, for we are dead in our trespasses and sins. And note that our faith has a specific object- as He is offered to us in the gospel.”
Second, faith, by its nature, is passive. We rest; we do not work. We receive; we do not earn. There is more to resting than mere assent, but there is not more work. Indeed there is no work at all, just resting and receiving the very ground of our salvation- the work of Christ for us.
Rest. Receive. And rejoice.