I. They are very sinful and will not be reformed, v. 22. These are the words of God himself, for so the prophet chose to give this character of the people, rather than in his own words, or as from himself: My people are foolish. God calls them his people, though they are foolish. They have cast him off, but he has not cast them off, Rom. xi. 1. "They are my people, whom I have been in covenant with, and still have mercy in store for. They are foolish, for they have not known me." Note, Those are foolish indeed that have not known God, especially that call themselves his people, and have the advantages of coming into acquaintance with him, and yet have not known him. They are sottish children, stupid and senseless, and have no understanding. They cannot distinguish between truth and falsehood, good and evil; they cannot discern the mind of God either in his word or in his providence; they do not understand what their true interest is, nor on which side it lies. They are wise to do evil, to plot mischief against the quiet in the land, wise to contrive the gratification of their lusts, and then to conceal and palliate them. But to do good they have no knowledge, no contrivance, no application of mind; they know not how to make a good use either of the ordinances or of the providences of God, nor how to bring about any design for the good of their country. Contrary to this should be our character. Rom. xvi. 19, I would have you wise unto that which is good, and simple concerning evil.