The Holy One does not argue with Moses. He simply issues a new set of orders. Targum Pseudo-Jonathan preserves the dual commission: the Lord spake with Mosheh and with Aharon, and gave them admonition for the sons of Israel, and sent them to Pharoh, king of Mizraim, to send forth the children of Israel from the land of Mizraim.
Notice the two audiences. First, admonition for the sons of Israel. The slaves, who had failed to hear Moses' five-verb speech, will now receive something sharper — an admonition. The Aramaic word pikuda suggests a command rather than a consolation. The time for coaxing has ended.
One Commission, Two Directions
And second, sent them to Pharoh. The same two brothers carry the same Word in opposite directions. To Israel, the admonition is: believe, prepare, be ready. To Pharaoh, the message is: send them forth.
The Targum's verb spake with (rather than spake to) is deliberate. The Holy One does not lecture Moses and Aaron from above; He speaks with them — a collaborative briefing. The leadership of the Exodus is a partnership between heaven and two brothers, and the Targum carefully preserves that partnership language.
The sages of the Targumic tradition see this verse as the hinge between the failed first attempt and the plague sequence that follows. Moses had despaired. God does not address the despair directly. He simply issues new assignments. The despair, left behind by the weight of the mission, dissolves under the force of renewed commission.
The takeaway: when prayer becomes paralysis, the Jewish imagination prescribes movement. The Holy One does not always answer Moses' how? with explanation. Sometimes He answers with a new task and the expectation that the doing will outpace the doubting. The Exodus is about to begin because two brothers stopped asking questions and started walking.