James: See “James, Brother of Jesus” Profile.
By calling his readers the twelve tribes, James connects Christianity to the history of Israel. The exile to Babylon scattered the twelve tribes. But Jewish interpreters hoped God would reunite them (see Psalms of Solomon 17:26–28; Testament of Benjamin 9:2; compare Ezekiel 37:15–28; Matthew 19:28). Christ has spiritually ended Israel’s exile and reunited the tribes.
the Dispersion (Greek diaspora): Jews scattered abroad were living outside Palestine (John 7:35; Acts 2:5; 8:1; 11:19).
Greetings (Greek chairein): This was a common greeting in first-century Greek letters and in personal interactions (Acts 15:23; 23:26; Matthew 26:49; Luke 1:28).