James 2:8 - Ellicott's Commentary On The Whole Bible

If ye fulfil the royal law. — Better paraphrased thus, If, however, ye are fulfilling the Law, as ye imagine and profess ye are doing, the royal law, according to the Scripture, “Thou shalt love thy neighbour as thyself, ye are doing well; but.... Mark the touch of irony in the defence which St. James puts into the mouths of his hearers. It were certainly a sweet proof of neighbourly affection, that exemplified in James 2:3. The “royal,” or “kingly law,” is, of course, God’s, in its highest utterance; and may be taken as an illustration of what a law really consists: viz., a command from a superior, a duty from an inferior, and a sanction or vindication of its authority. There is much confusion of thought, both scientific and theological, with regard to this; were it not so we should hear less of the “laws of nature,” and divers other imaginary codes which the greatest legist of modern times has called “fustian.” The sovereign law of love, thus expressed by the Apostle, is one so plain that the simplest mind may be made its interpreter; and the violation of it is at once clear to the offender.