“The Lord spoke to Moses and to Aaron, and commanded them concerning the children of Israel and concerning Pharaoh king of Egypt, to take the children of Israel out of the land of Egypt” (Exodus 6:13). “The Lord spoke to Moses and to Aaron, and commanded them concerning the children of Israel” – that is what is written: “In all toil there is profit, but the talk of the lips brings only lack” (Proverbs 14:23).
For all matters in which a person expends effort for the sake of Torah, he is rewarded. Could it be so even in matters of futility? The verse states: “But the talk of the lips brings only lack.” You find that Joseph was deserving to be placed in prison for only ten years because he slandered his ten brothers; but because he said to the butler: “If only you remember me with you…and mention me to Pharaoh” (Genesis 40:14), two additional years were added for him, as it is stated: “It was at the end of two years” (Genesis 41:1).
Likewise you find in Moses’s regard; initially, he was worthy to have the divine speech commune with him by himself, but because he said: “Please…send by means of whom You will send” (Exodus 4:13), it was stated to him: “Is there not Aaron your brother the Levite?” (Exodus 4:14). Here, too, “[Moses spoke before the Lord saying:] Behold, the children of Israel did not heed me…” (Exodus 6:12); he was worthy to have all the miracles performed through him, but because of this the divine speech communed with [both] him and Aaron, as it is stated: “The Lord spoke to Moses and to Aaron.”