Ver. 21. Was not Abraham … justified by works? We may observe, that S. James here brings the very same examples of Abraham and Rahab, which it is likely he knew some had miscontrued in S. Paul, as if the great apostle of the Gentiles had taught that faith alone was sufficient to salvation. But S. Paul neither excludes good works done by faith, when he commends faith, excluding only the works of the law of Moses, as insufficient to a true justification. See Rom. 3:27. And S. James by requiring good works does not exclude faith, but only teacheth that faith alone is not enough. This is what he clearly expresseth here in the 22d and in the 24th verse. Man, says he, is justified, and not by faith only. And (v. 22) seest thou that faith did co-operate with Abraham’s works, and by works faith was made perfect. In fine, we must take notice, that when S. James here brings the example of Abraham offering his son Isaac, to shew that he was justified by works, his meaning is not that Abraham then began first to be justified, but that he then received an increase of his justice. He was justified at least from his first being called, and began then to believe and to do good works. It is true his faith was made perfect, and his justice increased, when he was willing to sacrifice his son
Haydock, G. L. (1859). Haydock’s Catholic Bible Commentary (Jas 2:21). New York: Edward Dunigan and Brother.