The Catholic Church affirms James 2:24 ('a person is justified by works and not by faith alone') as a defining Scripture for understanding the relationship between faith and works in justification. This passage stands at the heart of the Catholic-Protestant divide following the Reformation. The Council of Trent (1547) explicitly affirmed that justification is 'not by faith alone,' and modern Catholic documents maintain this position. The Catechism of the Catholic Church (§§ 2083-2087) teaches that true faith must bear fruit in good works and that love of neighbor is inseparable from faith.

Catholic theology interprets James as complementing Paul's doctrine of justification by faith: Paul emphasizes that justification is by grace through faith (not by works of the law), while James emphasizes that saving faith must be living faith, demonstrated by obedience and charity. The sacraments, particularly penance and the Eucharist, are understood as the ordinary means by which God imparts grace and by which the faithful cooperate with grace through the practice of virtue and good works.