tn The verb שִׂים (sim) means “to place, put, set”; the sentence here more precisely says, “Who put a mouth into a man?”
sn The argumentation by Moses is here met by Yahweh’s rhetorical questions. They are intended to be sharp—it is reproof for Moses. The message is twofold. First, Yahweh is fully able to overcome all of Moses’ deficiencies. Second, Moses is exactly the way that God intended him to be. So the rhetorical questions are meant to prod Moses’ faith.
sn The final question obviously demands a positive answer. But the clause is worded in such a way as to return to the theme of “I AM.” Isaiah 45:5–7 developed this same idea of God’s control over life. Moses protests that he is not an eloquent speaker, and the Lord replies with reminders about himself and promises, “I will be with your mouth,” an assertion that repeats the verb he used four times in 3:12 and 14 and in promises to Isaac and Jacob (Gen 26:3; 31:3).