Short answer
– Most evangelicals identify the author of James 1:5 (and the whole epistle) as “James the Just,” the leader of the Jerusalem church and the brother (or close kinsman) of Jesus. He is commonly understood to be the historical James mentioned in Galatians 1:19 and in the Gospels (e.g., Matthew 13:55).

Why evangelicals favor James the Just as the author
– The letter itself names “James” (James 1:1) and has a Jewish-Christian, wisdom-teaching character that fits a Jerusalem leader addressing Jewish believers.
– Early church testimony attributes the epistle to James the brother of the Lord (Clement of Alexandria, Origen, Eusebius and others preserve this tradition).
– Historical context fits an early date (likely before the destruction of Jerusalem, often placed in the 40s–60s AD), when James was leader of the Jerusalem church and influential in Jewish-Christian circles (cf. Acts 15:13–21).
– The Greek of James is good but carries Semitic/Hebrew thought-patterns and proverbial material (echoes of Proverbs), consistent with a Palestinian Jewish Christian author for a Jewish audience.

Who James the Just was (as understood in evangelical circles)
– Identity: Often called James the Just; called “brother of the Lord” in the New Testament (e.g., Galatians 1:19) — evangelicals vary on the precise meaning of “brother” (half-brother, step-brother, or close relative), but most hold he was a close blood relative of Jesus who became a Christian after the resurrection (1 Corinthians 15:7 is often cited).
– Role: A leading elder in the Jerusalem church, respected for holiness and leadership; he played a prominent role in the Jerusalem council’s decisions (Acts 15) and is presented as a decisive figure in the early church.
– Character and ministry: Known for a practical, ethical teaching emphasis (fits the practical, pastoral tone of the epistle). Tradition and historians (e.g., Josephus, Hegesippus) record his influence and his martyrdom (commonly dated around AD 62), which fits an early authorship.

Why James 1:5 fits this author
– James 1:5 (“If any of you lacks wisdom, let him ask of God…”) matches the pastoral, wisdom-oriented teaching expected from a Jewish-Christian leader concerned with practical godly living.
– The exhortatory, communal tone (address to “the twelve tribes in the dispersion,” James 1:1) fits an elder writing to scattered Jewish believers.

Alternative views (brief)
– Some scholars have proposed other Jameses (e.g., James the son of Zebedee or James the son of Alphaeus) or later pseudonymous authorship. Evangelicals typically reject pseudonymous composition and hold the traditional attribution to James the Just as the most likely and trustworthy view.

Theological note from an evangelical perspective
– Evangelicals see James as a genuinely apostolic-era, authoritative Christian teacher whose practical counsel (including James 1:5) is Scripture—God-breathed and applicable for Christian living. His emphasis on asking God for wisdom, persevering through trials, and living out faith in concrete works is read as complementary to Paul’s theology, not contradictory.

If you’d like, I can:
– Give a fuller summary of the historical evidence (early church writers and Josephus),
– Outline the main arguments for and against James’s authorship in more detail, or
– Provide a short devotional reflection on James 1:5 from an evangelical perspective.