The differences between Paul and James are more apparent than real – especially when one takes a step back to look at the bigger picture. Their supposed ‘conflict’ can be sustained only by picking out a few selected passages in Paul’s letters, while ignoring what he also wrote about translating faith into action (e.g. Galatians 5:6; I Thessalonians 1:3; Colossians 1:3,4). He is particularly clear on this point in those very letters (Romans and Galatians) where he has already discussed justification by faith alone at some length. So salvation is indeed through faith alone – but good works, for Paul as well as for James, are the proper outcome of genuine faith (e.g. Ephesians 2:8-10).
In fact, Paul and James are looking at the subject of justification from different angles; and so they emphasise different aspects of it. Paul focuses on the grounds for a person’s justification; in this context, faith and ‘works of the law’ are mutually exclusive (Galatians 2:16). James, on the other hand, is interested in the evidence for a person’s justification (James 2:14,18); hence his two alternatives are not ‘faith’ and ‘works’, but ‘faith with works’ and ‘faith without works’.
Paul lays down the fundamental principle of justification by faith; James applies a necessary corrective to those who might be tempted to talk exclusively about faith and thus imply that good works do not matter. Ultimately there is no conflict between these two apostles; their teachings are complementary.