He shall be to thee instead of a mouth; and thou shalt be to him instead of God.— The meaning of this is very evident from the context, without recourse to those subtleties and vain distinctions which some have made. "Thou shalt be to him a God, in the same manner as he shall be to thee, a mouth; thou shalt give commands to him, as I, the Lord God, Jehovah Aleim, give commands to thee: he shall deliver thy commands, and be thy mouth in the same manner, as men are, as it were, the mouth of God, when they deliver his commands. He shall be thy organ, or minister, to publish thy orders to the people; and thou shalt be his oracle, to deliver to him the mind and will of thy God." See Exodus 4:30 and ch. Exodus 7:1. Diodorus Siculus has preserved a tradition, that Moses received his laws from a God, called Iao, that is, Jehovah.
Note; 1. If God does not teach the most eloquent Orator, and bless his discourses, he will only speak to the air, or at best to the ear, not to the heart. But, 2. Moses must take his rod. His works shall speak more than his words. And a minister's life, like this rod, will give the greatest weight to his discourses.