2 If you refuse to let them go, I will plague your whole country with frogs. 3 The river shall swarm with frogs; they shall come up into your palace, into your bedchamber and your bed, and into the houses of your officials and of your people, and into your ovens and your kneading bowls. 4 The frogs shall come up on you and on your people and on all your officials.' " 5 And the Lord said to Moses, "Say to Aaron, "Stretch out your hand with your staff over the rivers, the canals, and the pools, and make frogs come up on the land of Egypt.' " 6 So Aaron stretched out his hand over the waters of Egypt; and the frogs came up and covered the land of Egypt. 7 But the magicians did the same by their secret arts, and brought frogs up on the land of Egypt.
Matthew Henry's Commentary on Exodus 8:2-7
Commentary on Exodus 8:1-15
(Read Exodus 8:1-15)
Pharaoh is plagued with frogs; their vast numbers made them sore plagues to the Egyptians. God could have plagued Egypt with lions, or bears, or wolves, or with birds of prey, but he chose to do it by these despicable creatures. God, when he pleases, can arm the smallest parts of the creation against us. He thereby humbled Pharaoh. They should neither eat, nor drink, nor sleep in quiet; but wherever they were, they should be troubled by the frogs. God's curse upon a man will pursue him wherever he goes, and lie heavy upon him whatever he does. Pharaoh gave way under this plague. He promises that he will let the people go. Those who bid defiance to God and prayer, first or last, will be made to see their need of both. But when Pharaoh saw there was respite, he hardened his heart. Till the heart is renewed by the grace of God, the thoughts made by affliction do not abide; the convictions wear off, and the promises that were given are forgotten. Till the state of the air is changed, what thaws in the sun will freeze again in the shade.