The following is a quote from John Gerstner's Primer on Roman Catholicism:
Martin Luther, the great reformer, while still a Roman Catholic, had an experience which was the cue to his whole career. It occurred, according to his son, Paul, when, mounting the holy staircase of Rome on his knees in penance, he realized in a sudden flash of understanding the meaning of these words: â€œThe just shall live by faith,â€ Romans 1:17. Immediately he rose from his knees and walked down the steps. This was the prelude to the Reformation. Was Luther right? Are men justified before God by faith alone? Let us see.
According to the Bible, justification is by faith in Christ; according to Rome, justification is by faith plus works. According to the Bible, justification produces good works; according to Rome, good works produce justification. According to the Bible, justification is by Christ alone; according to Rome, it is by Christ and the sinner. It would appear that the word of Rome and the Word of God are two different things. The following is a formula I have used for over 50 years when explaining this point:
Roman Catholic Teaching:
Faith + Works â†’ Justification
Faith â†’ Justification + Works
It can be seen from the diagram that works are necessary for justification in both systems; but in the Roman system they are necessary as a prerequisite; in the biblical system they are necessary as a postrequisite.
(For a much fuller treatment of this entire issue, see the book Justification by Faith ALONE, by John MacArthur, R. C. Sproul, John Armstrong, Joel Beeke, and myself, and published by Soli Deo Gloria in 1995.)
But someone will ask, does the Bible not also state that â€œfaith without works is deadâ€ (James 2:20)? Does it not go on to say that such a faith cannot justify? Does it not imply that faith must be supplemented by works in order to avail? Is the Catholic doctrine not right after all: justification is by faith plus works? The answer is simpleâ€”justification is by a living and active faith (this is understood everywhere in the Bible; it is made explicit in James). Now, a living faith leads to good works. So justification, which is by a living faith, is by a full-of-the-promise-of-good-works faith. â€œJustification is by faith alone, but not by the faith that is alone.â€
Let us endeavor to illustrate what James is teaching here about faith. He is not questioning the ability of genuine faith to justify, but he is simply insisting that it has to be genuine and not â€œdeadâ€ faith. Suppose a man were fortunate enough to have $35 to spend on a hat and went to a store to purchase one. Having selected the one he wished, he hands the salesman his currency only to be told that it is counterfeit and cannot be accepted for payment. Is the dealer saying that the hat cannot be bought for $35? That something more is needed? Is he reflecting on the previously advertised ability of $35 to buy the hat in question? Certainly not. He is only insisting that it be genuine currency. That is all that is necessary, but it is necessary. In the same way, James is saying that justification is not by a counterfeit faith. He is not saying that it is not by genuine faith.
â€œJustification by faithâ€ is really not the precise statement of this doctrine. Justification is by CHRIST ALONE (received by faith). We are not justified by our acceptance of the redeeming mercy of Jesus Christ crucified, but by Christâ€™s mercy (ours by acceptance).
This is the heart of our doctrineâ€”that Christ alone was sufficient for all our sins, that He is able to save to the uttermost those who come to Him in faith. And, conversely, the most serious part of the Roman heresy on this whole doctrine is at this point. By denying justification by faith alone she also denies the sufficiency of Christâ€™s atonement.
We have observed that justification is by faith in Christ. Now let us note that justification is by faith in Christ. Christ is the ground of justification; faith is the instrument. Christ saves; faith is the means by which Christâ€™s salvation is received. There is no other name than His whereby we must be saved; but there is no other way than by faith. A. H. Strong has likened faith to the coupling which connects a locomotive with its train of cars. It is the locomotive and not the coupling that pulls the train. But without the coupling even the locomotive could not pull the train. It is Christ and not faith that saves the soul. But without faith in Him not even Christ is able to save. (And remember, faith in Christ is the gift of Christ.)
Some fancy that biblical justification is a process rather than an act because it is mentioned at different times in a justified personâ€™s life. But its being stated at different times is because different â€œworksâ€ illustrate its continuing activity. It is cited in connection with Abrahamâ€™s later offering of Isaac, not because he did not possess it earlier, but because that great â€œworkâ€ demonstrated Abrahamâ€™s faith (which alone justified him, and not that or any other work). As James said, the work justified (vindicated) the faith (which justified the person).
One concluding word on the fruits of justification. Rome has always charged that this Protestant doctrine leads to immorality. Being justified by faith, Rome says, we have a presumptuous peace with God; we have access into a grace from which we will constantly fall; and we are conceitedly assured of heaven and can find no purpose in tribulation and discipline. But Paul says, â€œBeing justified by faith, we have peace with God through our Lord Jesus Christ: by whom also we have access by faith into this grace wherein we stand, and rejoice in the hope of the glory of God. And not only so, but we glory in tribulation also,â€ Romans 5:1â€“3. Rome, of course, is thinking of a â€œcounterfeitâ€ grace while the Bible speaks of the genuine product. History shows that where the doctrine of justification by faith alone has been preached in its purity, morals have been most rigorous, Christianity most abiding, and good works most abundant. And why should it not be so, seeing we have been redeemed by the precious blood of Christ?
Furthermore, â€œfaith without works is dead.â€ No works, no faith. No faith, no justification. Protestantism has always been anti-antinomian.