James 4:12

12There is one lawgiver (134) Now he connects the power of saying and destroying with the office of a lawgiver, he intimates that the whole majesty of God is forcibly assumed by those who claim for themselves the right of making a law; and this is what is done by those who impose as a law on others their own nod or will. And let us remember that the subject here is not civil government, in which the edicts and laws of magistrates have place, but the spiritual government of the soul, in which the word of God alone ought to bear rule. There is then one God, who has consciences subjected by right to his own laws, as he alone has in his own hand the power to save and to destroy.

It hence appears what is to be thought of human precepts, which cast the snare of necessity on consciences. Some indeed would have us to shew modesty, when we call the Pope antichrist, who exercises tyranny over the souls of men, making himself a lawgiver equal to God. But we learn from this passage something far more, even that they are the members of Antichrist, who willingly submit to be thus ensnared, and that they thus renounce Christ, when they connect themselves with a man that is not only a mortal, but who also extols himself against him. It is, I say, a prevaricating obedience, rendered to the devil, when we allow any other than God himself to be a lawgiver to rule our souls.

Who art thou. Some think that they are admonished here to become reprovers of their own vices, in order that they might begin to examine themselves, and that by finding out that they were not purer than others, they might cease to be so severe. I think that their own condition is simply suggested to men, so that they may think how much they are below that dignity which they assumed, as Paul also says, “Who art thou who judgest another?” (Romans 14:4.)