EXPOSITION
THE FIRST SIGN, AND ITS FAILURE TO CONVINCE. Obeying the command given them (Exodus 7:2, Exodus 7:9), Moses and Aaron went to the court a second time, and entering into the royal presence, probably repeated their demand—as from God—that the king would let the Children of Israel go (Exodus 6:11), when Pharaoh objected that they had no authority to speak to him in God's name, and required an evidence of their authority, either in the actual words of Exodus 7:9 ("Shew a miracle for you"), or in some equivalent ones. Aaron hereupon cast down on the ground the rod which Moses had brought from Midian, and it became a serpent (Exodus 7:10). Possibly Pharaoh may have been prepared for this. He may have been told that this was one among the signs which had been done in the sight of the elders and people of Israel when the two brothers first came back from Midian (Exodus 4:30). If he knew of it, no doubt the "magicians" knew of it, and had prepared themselves. Pharaoh summoned them, as was natural, to his presence, and consulted them with respect to the portent, whereupon they too cast down the rods which they were carrying in their hands, and they "became serpents; but Aaron's rod swallowed up their rods" (Exodus 7:12). (For the explanation of those facts, see the comment below). Pharaoh was to some extent impressed by the miracle, but not so as to yield. His heart remained hard, and he refused to let the people go.