There are two judgments under consideration here. There is first the judgment of men described in verse 1, full of partiality and selectivity; and then there is God’s perfect judgment which shows partiality to no one.
Human justice ought to be based on the Ten Commandments. They are the standard by which God will judge the whole world on the last day. Whenever men act as judges, they anticipate that final judgment, or they should do so, for there is no other standard, and human judgment ought to be the implementation of God’s standards of justice in advance. What stops the man in view from judging himself is not lack of knowledge, but lack of honesty.
Here is someone who passes judgment on others, and yet does the very same things himself. What does he think is going to happen to him? Does he think he is going to survive the judgment of God? In order for that to happen, it would have to be true that God does not apply the same standard to all. It would have to be true that God has favourites, and that he is stricter towards some, and less strict towards others. Is that going to happen? Certainly not, says Paul. God’s judgment is according to truth, and truth does not adjust itself for the sake of certain favoured individuals. This is a most dangerous way to proceed, and yet so many do this. On what basis do they imagine God treats them differently from other people? If God did not spare his own Son, is he going to spare his enemies? Our false and partial judgment will be swept away by his true judgment.