4:10And Moses said unto the LORD, O my Lord, I am not eloquent, neither heretofore, nor since thou hast spoken unto thy servant: but I am slow of speech, and of a slow tongue.
4:11And the LORD said unto him, Who hath made man’s mouth? or who maketh the dumb, or deaf, or the seeing, or the blind? have not I the LORD?
4:12Now therefore go, and I will be with thy mouth, and teach thee what thou shalt say.
4:13And he said, O my Lord, send, I pray thee, by the hand of him whom thou wilt send.
4:14And the anger of the LORD was kindled against Moses, and he said, Is not Aaron the Levite thy brother? I know that he can speak well. And also, behold, he cometh forth to meet thee: and when he seeth thee, he will be glad in his heart.
4:15And thou shalt speak unto him, and put words in his mouth: and I will be with thy mouth, and with his mouth, and will teach you what ye shall do.
4:16And he shall be thy spokesman unto the people: and he shall be, even he shall be to thee instead of a mouth, and thou shalt be to him instead of God.
4:17And thou shalt take this rod in thine hand, wherewith thou shalt do signs.
A burning bush would not keep its audience for long if it simply finished burning. What arrests Moses is the contradiction: the flame is real, and the bush remains. He turns aside to investigate, and the Book of Exodus carefully places the call after that movement. The sight draws him away from his route; the voice addresses him by name. This is no longer an unusual feature of the landscape.
The wording moves from the angel of the LORD to the LORD and then to God, all within the same encounter. The text binds the messenger's appearance to the divine speech without pausing to explain that relationship in later theological categories. Moses, Moses makes the address unmistakably personal, while Here am I answers a summons before its contents have been disclosed. The shepherd who turned aside to understand a fire is being addressed about Israel. The bush is not impressive architecture, and it has no inscription identifying its importance. Its significance is that God is speaking from it.