FROG (צְפַרְדֵּעַ, H7630; Βάτραχος. Frog in all Eng. VSS).
The only OT mention of this common amphibian is concerning the cause of the second plague. Many species are found in the marshes and rivers of the Middle E and the Nile Valley, the most common being Rana esculenta, the Edible or Green Frog. It is sometimes known as the River Frog because it stays in water most of the year and not only in the breeding season. It reaches a length of about three inches. Many people dislike the cool moist feel of a frog’s skin, but the reaction of the Egyptians was far more severe, because to them the frog was also unclean. This finds an echo in the only NT occurrence (Rev 16:13). This plague followed closely on the first, by which the Nile became gravely polluted. This may be seen as the immediate cause of the frogs leaving the rivers and invading the houses. The magicians could produce frogs by sleight of hand, but could not drive away the plague that God had sent. In the hot dry air frogs quickly became dehydrated and died, the result being physically unpleasant as well as abhorrent. It is ironic that frogs are useful in keeping down insects, such as caused the following plagues.
International Standard Bible Encyclopedia (1915)
(tsephardea`; compare Arabic dafda` (Ex 8:2 ff; Ps 78:45; 105:30); batrachos (Re 16:13)): The references in Psalms, as well as in Exodus, are to the plague of flogs. In Re 16:13 we have, "And I saw coming out of the mouth of the dragon, and out of the mouth of the beast, and out of the mouth of the false prophet, three unclean spirits, as it were frogs." The word tsephardea` probably referred both to frogs and to toads, as does the Arabic dafda`. In Palestine and Syria Rana esculenta, Bufo viridis and Hyla arborea are common. According to Mr. Michael J. Nicoll, assistant director of the Zoological Gardens at Gizah, near Cairo, the commonest Egyptian species are Rana mascariensis and Bufo regularis. Rana esculenta, Bufo viridis and Bufo vittatus are also found, but are much less common.