Exodus 8:11-15

11The 1frogs will depart from you and your houses and your servants and your people; they will be left only in the Nile.” 12Then Moses and Aaron went out from Pharaoh, and 2Moses cried to the Lord concerning the frogs which He had 3inflicted upon Pharaoh. 13The Lord did according to the word of Moses, and the frogs died out of the houses, the courts, and the fields. 14So they piled them in heaps, and the land 4became foul. 15But when Pharaoh saw that there was relief, he 5hardened his heart and 6did not listen to them, as the Lord had said.