Midrasch zu Schemot 10:15

Whatever the Egyptians devised against Israel, [the Holy One] brought against them. Those < Egyptians > devised for them to draw their water. What is written (in Ps. 78:44)? HE TURNED THEIR NILES INTO BLOOD SO THAT THEIR STREAMS WERE UNDRINKABLE. Those < Egyptians > devised for them to be laden as traveling traders.²²Gk.: pragmateutes. He sent frogs upon them and covered them with resin. Those < Egyptians > devised for them to work on the land. The Holy One made the land swarm with gnats. Those <Egyptians> devised that they should bear their children as a paidagogos.²³The Greek word designates a slave who was assigned to a child as an attendant and guardian. He sent lions, wolves, and bears among them. <If> an Egyptian had ten children, when he told Israel to bring them to the market place, the lion came and took one, the wolf one, the bear one, the leopard one, and the snake one. Then he came <back> to the Egyptian alone. The Egyptian said: Where are my children? Israel said to him: Sit down and I myself will render you an accounting: The lion took one <etc.>; and so <he continued> on, until he had given him an accounting. Now they (the Egyptians) devised that they would tend their livestock, but he sent out the plague among them, as stated (in Exod. 9:6): THEN ALL THE EGYPTIAN LIVESTOCK DIED. They intended that they would be bath attendants {bathe them}. He brought the boils upon them. They intended to stone them with stones. The Holy One brought the hail upon them, as stated (in Exod. 9:22): THAT THERE MAY BE HAIL <IN ALL THE LAND OF EGYPT >…. They intended that they would be their vine dressers. The Holy One brought the locusts, who ate their trees, as stated (in Exod. 10:15): AND THEY ATE ALL THE GRASS OF THE EARTH…. They intended to imprison them in prison. The Holy One brought darkness upon them, as stated (in Exod. 10:23): THEY COULD NOT SEE ONE ANOTHER…. They intended to kill them. The Holy One killed their first-born, as stated (in Exod. 12:29): THAT THE LORD SMOTE ALL THE FIRST-BORN. They intended to drown them in water. The Holy One also drowned them in water, as stated (in Ps. 136:15): BUT OVERTHREW PHARAOH AND HIS HOST IN THE REED SEA….

"And YHVH said to Moses, 'Hold out your hand...'" (Exodus 10:12) - Why did He bring locusts upon them? Because the had made Israel sowers of wheat and barley, therefore He brought upon them locusts and they ate all that Israel had sown for them. "And Moses held out his staff [over the land of Egypt, and YHVH drove an east wind over the land all that day and the night]..." (Exodus 10:13) Why did the Holy One Blessed Be He make the time for the plagues tomorrow and He didn't bring them immediately? So that they would turn back through them and they would do repentance. "And the locusts went up..." (Exodus 10:14) "And they covered the view of the entire land..." (Exodus 10:15) "And Pharaoh hurried to call to Moses and to Aaron..." (Exodus 10:16) What is "I have sinned to YHVH your God and to you"? "I have sinned to YHVH your God" - that I did not let Israel go. "and to you" - that I threw you out from before me, and that I thought to curse you, as I said "YHVH be with you the same..." (Exodus 10:10). "And now, forgive my offense..." (Exodus 10:17) "And he went out from Pharaoh's presence..." (Exodus 10:18).