Cross reference
Exodus 8:2
2 And if thou refuse to let them go, behold, I will smite all thy borders with frogs:
Exodus 7:14
14 And the LORD said unto Moses, Pharaoh's heart is hardened, he refuseth to let the people go.
Exodus 9:2
2 For if thou refuse to let them go, and wilt hold them still,
Psalms 78:45
45 He sent divers sorts of flies among them, which devoured them; and frogs, which destroyed them.
Psalms 105:30
30 Their land brought forth frogs in abundance, in the chambers of their kings.
Revelation 16:13-14
13 And I saw three unclean spirits like frogs come out of the mouth of the dragon, and out of the mouth of the beast, and out of the mouth of the false prophet.
14 For they are the spirits of devils, working miracles, which go forth unto the kings of the earth and of the whole world, to gather them to the battle of that great day of God Almighty.