The most serious problem these verses pose is the question of what James 2:24 means: "You see that a man is justified by works, and not by faith alone." Some imagine that this contradicts Paul in Romans 3:28: "For we maintain that a man is justified by faith apart from works of the Law." John Calvin explained this apparent difficulty:
It appears certain that [James] is speaking of the manifestation, not of the imputation of righteousness, as if he had said, Those who are justified by faith prove their justification by obedience and good works, not by a bare and imaginary semblance of faith. In one word, he is not discussing the mode of justification, but requiring that the justification of all believers shall be operative. And as Paul contends that men are justified without the aid of works, so James will not allow any to be regarded as Justified who are destitute of good works ... Let them twist the words of James as they may, they will never extract out of them more than two propositions: That an empty phantom of faith does not justify, and that the believer, not contented with such an imagination, manifests his justification by good works. [Henry Beveridge, trans., John Calvin, Institutes of the Christian Religion 3:17:12 (Grand Rapids: Eerdmans, 1966 reprint), 2: 115.]
James is not at odds with Paul. "They are not antagonists facing each other with crossed swords; they stand back to back, confronting different foes of the gospel." [Alexander Ross, "The Epistle of James and John," The New International Commentary on the New Testament (Grand Rapids: Eerdmans, 1954), 53.] In 1:17-18, James affirmed that salvation is a gift bestowed according to the sovereign will of God. Now he is stressing the importance of faith's fruit—the righteous behavior that genuine faith always produces. Paul, too, saw righteous works as the necessary proof of faith.
Those who imagine a discrepancy between James and Paul rarely observe that it was Paul who wrote, "Shall we sin because we are not under law but under grace? May it never be!" (Rom. 6:15); and "Having been freed from sin, you became slaves of righteousness" (v. 18). Thus Paul condemns the same error James is exposing here. Paul never advocated any concept of dormant faith.
When Paul writes, "by the works of the Law no flesh will be justified in His sight," (Rom. 3:20),
he is combatting a Jewish legalism which insisted upon the need for works to be justified; James insists upon the need for works in the lives of those who have been justified by faith. Paul insists that no man can ever win justification through his own efforts ... James demands that a man who already claims to stand in right relationship with God through faith must by a life of good works demonstrate that he has become a new creature in Christ. With this Paul thoroughly agreed. Paul was rooting out 'works' that excluded and destroyed saving faith; James was stimulating a sluggish faith that minimized the results of saving faith in daily life. [D. Edmond Hiebert, The Epistle of James (Chicago: Moody, 1979), 175.]
James and Paul both echo Jesus' preaching. Paul's emphasis is an echo of Matthew 5:3: "Blessed are the poor in spirit, for theirs is the kingdom of heaven." James's teaching has the ring of Matthew 7:21: "Not everyone who says to Me, 'Lord, Lord,' will enter the kingdom of heaven; but he who does the will of My Father who is in heaven." Paul represents the beginning of the Sermon on the Mount; James the end of it. Paul declares that we are saved by faith without the deeds of the law. James declares that we are saved by faith, which shows itself in works. Both James and Paul view good works as the proof of faith—not the path to salvation.
James could not be more explicit. He is confronting the concept of a passive, false "faith," which is devoid of the fruits of salvation. He is not arguing for works in addition to or apart from faith. He is showing why and how, true, living faith always works. He is fighting against dead orthodoxy and its tendency to abuse grace.
The error James assails is faith without works; justification without sanctification; salvation without new life.
Again, James echoes the Master Himself, who insisted on a theology of lordship that involved obedience, not lip-service. Jesus chided the disobedient ones who had attached themselves to Him in name only: "Why do you call Me, 'Lord, Lord,' and do not do what I say?" (Luke 6:46). Verbal allegiance, He said, will get no one to heaven: "Not everyone who says to Me, 'Lord, Lord,' will enter the kingdom of heaven; but he who does the will of My Father who is in heaven" (Matt. 7:21).
That is in perfect harmony with James: "Prove yourselves doers of the word, and not merely hearers who delude themselves" (1:22); for "faith, if it has no works, is dead, being by itself" (2:17).