What James communicates in the second chapter of his letter does not invalidate what Paul fastidiously communicates regarding justification by faith alone in the third through fifth chapters of Romans.
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Both Paul and James cite Abraham as an example. But Paul clearly points out that Abraham was justified, or reckoned righteous, by God through faith long before he “offered up Isaac on the altar,” the event James illustrates in his argument (see Ja. 2:21). In fact, Paul points out that Abraham was “reckoned righteous” even before he was circumcised, some 20 years before the actual event with Isaac (Rom. 4:10-11).
James does not deviate from faith to works as the justifying agent when he illustrates Abraham and Isaac as an example, as Beck clearly translates verse 24: “You see his faith was active with works and by works reached its goal.” In other words, Abraham did not simply have a “said” faith, but a true faith which was demonstrated in his life by works. Yet, it was not the works that justified him, but his faith which motivated and produced works, even twenty some years after he believed God and it was reckoned to him as righteousness (Rom. 4:5).
A man of true faith, opposed to a “said” faith, will ALWAYS demonstrate works in his life. That’s why James concludes, “For just as the body without the spirit is dead, so also faith without works is dead” (i.e., a mere “said” faith). As the body is animated by the spirit, faith is animated by works. And this takes us right back to James’ original statement, "I will SHOW you my faith by my works.
The legalist always distorts James and tries to put him at odds with Paul. But the astute believer sees that it’s actually the legalist who has the mere “said” faith, because, ultimately, he trusts in his own works to save and justify him before God – not the Person and work of Christ alone. Consequently, and quite contrary to Scripture, he believes (and teaches others, as well) that no one can actually know in this life time if they have eternal life. You see, a “said” is no faith at all.