v. 11. Speak not evil one of another, brethren. He that speaketh evil of his brother, and judgeth his brother, speaketh evil of the Law, and judgeth the Law; but if thou judge the Law, thou art not a doer of the Law, but a judge.
v. 12. There is one Lawgiver, who is able to save and to destroy; who art thou that judgest another?
The humility which is required of Christians will show itself not only in their behavior toward God, but also toward their neighbor. Against the commonest form of transgression in this respect the apostle writes: Do not speak against one another, brethren. The fact that the Christians are brethren is in itself a reason why they should not indulge in uncharitable criticism. For, as James explains: He that speaks against his brother, or judges his brother, speaks against the Law and judges the Law; but if thou judgest the Law, thou art not a doer of the Law, but a judge. To speak evil of a brother, to criticize and condemn one's brother in an uncharitable manner is against the will of God, against His holy Law, against the Eighth Commandment. A person, therefore, that becomes guilty of such behavior against his brother becomes guilty of a transgression of the Law. To say that the Law did not cover this case meant to misinterpret the Law, and this action, in turn, was equivalent to criticizing and condemning the Law. Surely, then, a person who presumed upon such conduct was not a doer of the Law, but a judge of the Law, and a poor one at that.
People that indulge in this pastime should remember: One it is who is Lawgiver and Judge, who is able to save and to destroy; but who art thou that judgest thy neighbor? Here the arrogant impertinence of one that judges his neighbor in an uncharitable manner is set forth. For he is presuming to discharge the functions of an office which belongs to God alone, since He it is that gave the Law, and He it is that will condemn the transgressors and punish the guilty. The passage reminds one strongly of Mat_7:1-5; Luk_6:37; Rom_2:1. For a mere man to criticize and condemn his neighbor, except in cases where the Lord Himself has charged the congregation with carrying out His condemnation, is altogether unwarranted, and is resented by God as an interference with His authority. The passage contains a warning which cannot be repeated too often.