John Calvin Commentary James 3:13

"Who is wise and understanding among you? let him show by his good life his works in meekness of wisdom." — James 3:13 (ASV)

Who is a wise man. Since the strong desire for slandering arises mostly from pride, and since a false conceit of wisdom for the most part generates pride, he therefore speaks here of wisdom. It is usual for hypocrites to exalt themselves and show off by finding fault with all others, as was formerly the case with many philosophers who sought glory for themselves through a bitter abuse of all other groups. James checked such haughtiness, with which slanderous men swell and by which they are blinded, by denying that the conceit of wisdom (with which men flatter themselves) has anything divine in it; on the contrary, he declares that it proceeds from the devil.

So, the meaning is that arrogant critics, who largely indulge themselves and at the same time spare no one, consider themselves very wise, but they are greatly mistaken. For the Lord teaches His people very differently—to be meek and courteous to others. Therefore, only those are wise in the sight of God who connect this meekness with upright conduct; for those who are severe and unyielding, though they may excel others in many virtues, do not yet follow the right way of wisdom.

But if ye have bitter envying (James 3:14). He points out the results that come from that extreme harshness which is contrary to meekness, for excessive severity necessarily produces harmful rivalries, which soon break out into conflicts. It is, indeed, an unusual way of speaking to place conflicts in the heart, but this does not affect the meaning; for the object was to show that the evil disposition of the heart is the source of these evils.

He has called envying, or emulation, bitter; for it prevails only when minds are so infected with the poison of malignity that they turn all things into bitterness.

So that we may then truly glory that we are the children of God, he instructs us to act calmly and meekly towards our fellow believers; otherwise, he declares that we are lying in claiming the Christian name. But it is not without reason that he has added the companion of envying, namely strife or contention, for conflicts and quarrels always arise from malignity and envy.