James’s constant use of this title, brethren, is the reminder that he is writing to us in terms of who and what we are in Christ Jesus. You could think of it as a shorthand. So when he says, brethren, he is reminding us that he is talking to us as those not only redeemed by Christ, but we are in the family of God. We are in union with Christ, thus in union and communion with one another. And so it is a term of great affection, a term of gospel hope.¹

Joseph A. Pipa