Obviously verse 9 stands in a relationship of contrast or opposition with verse 8. This can be seen in a double contrast: in the particles really (“indeed,” Living Bible) … But, and in the clauses you do well … you commit sin.

You show partiality: the verb is used only here in the New Testament. It is a verbal form of the noun used in 2.1. It means discrimination, that is “to treat people according to their outward appearance” (Good News Translation). In this context it refers to an act of flattering the rich (compare “But if you flatter the great,” Knox; “when you favour the rich,” New Jerusalem Bible).

You commit sin: for James favoritism is contradictory to the command to love and is therefore an act of sin. To show partiality is to commit sin. The verb you commit sin is a strong statement, literally “you are working sin,” indicating that the sinning is deliberate and intentional. It is certainly more than an error someone has fallen into, or merely some error that a person is guilty of, as the Good News Translation rendering may suggest. It is in fact overstepping the boundary to a willful disobedience of the will of God. The person who does this is a “transgressor” as is further defined in the next clause. In certain languages you commit sin will be expressed as “you have done something very wrong.”

The people who discriminate against the poor are convicted by the law as transgressors. The law is here spoken of as a witness exposing or a judge pronouncing the accused as guilty. The word law has been interpreted in two ways. Some have taken it as a reference to the “royal law” mentioned in 2.8, for it is argued that a person cannot fulfill the “royal law” and still show favoritism to the rich and discriminate against the poor. Others have understood it to mean the Mosaic Law of the Old Testament. This is apparently the sense intended by translations that render it as “Law” (so Goodspeed, Phillips, and Good News Translation). Biblia Dios Habla Hoy has rendered it as “the law of God.” People who know the law and yet willfully disobey it are to be convicted or “condemned” by the law. They are transgressors, “offenders” (Revised English Bible) of the law, and therefore “law-breakers” (Goodspeed). The word rendered convicted is a present passive participle and therefore can be rendered as “stand convicted” (so Goodspeed, Revised English Bible) or “stand condemned.” In languages where there is no difficulty having an impersonal law convicting someone, it is possible to render the phrase as Good News Translation has done, “the Law condemns you as a lawbreaker.” Otherwise one of the following may be required: “what God commands in the Law shows that you have sinned” or “according to the words written in God’s book, you have sinned.”

Quoted with permission from Loh, I-Jin and Hatton, Howard A. A Handbook on The Letter from James. (UBS Handbook Series). New York: UBS, 1997. For this and other handbooks for translators see here .