Here, I. The prophet is ordered to address himself to the Ammonites, in the name of the Lord Jehovah the God of Israel, who is also the God of the whole earth. But what can Chemosh, the god of the children of Ammon, say, in answer to it? He is bidden to set his face against the Ammonites, for he is God's representative as a prophet, and thus he must signify that God set his face against them, for the face of the Lord is against those that do evil, Ps. xxxiv. 16. He must speak with boldness and assurance, as one that knew whose errand he went upon, and that he should be borne out in delivering it. He must therefore set his face as a flint, Isa. i. 7. He must show his displeasure against these proud enemies of Israel, and face them down, though they were very impudent, and thus must show that, though he had prophesied so much and so long against Israel, yet still he was for Israel, and, while he witnessed against their corruptions, he adhered to and gloried in God's covenant with them. Note, Those are miserable that have the preaching and praying of God's prophets against them, against whom their faces are set.