Adam Clarke's Bible Commentary Verse 5. Stretch forth thine hand-over the streams, over the rivers] The streams and rivers here may refer to the grand divisions of the Nile in the Lower Egypt, which were at least seven, and to the canals by which these were connected; as there were no other streams, &c., but what proceeded from this great river.
Matthew Henry Commentary
Verses 1-15 - Pharaoh is plagued with frogs; their vast numbers made them sor 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 thes despicable creatures. God, when he pleases, can arm the smallest part of the creation against us. He thereby humbled Pharaoh. They shoul 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 wil 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 wa respite, he hardened his heart. Till the heart is renewed by the grac of God, the thoughts made by affliction do not abide; the conviction 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.
Original Hebrew ויאמר559 יהוה3068 אל413 משׁה4872 אמר559 אל413 אהרן175 נטה5186 את853 ידך3027 במטך4294 על5921 הנהרת5104 על5921 היארים2975 ועל5921 האגמים98 והעל5927 את853 הצפרדעים6854 על5921 ארץ776 מצרים׃4714