1 sn The text stresses that the water in the Nile, and Nile water that had been diverted or collected for use, was polluted and undrinkable. Water underground also was from the Nile, but it had not been contaminated, certainly not with dead fish, and so would be drinkable.
2 sn An attempt to connect this plague with the natural phenomena of Egypt proposes that because of the polluted water due to the high Nile, the frogs abandoned their normal watery homes (seven days after the first plague) and sought cover from the sun in homes wherever there was moisture. Since they had already been exposed to the poisonous water, they died very suddenly. The miracle was in the announcement and the timing, i.e., that Moses would predict this blow, and in the magnitude of it all, which was not natural (Greta Hort, “The Plagues of Egypt,” ZAW 69 : 95-98). It is also important to note that in parts of Egypt there was a fear of these creatures as embodying spirits capable of great evil. People developed the mentality of bowing to incredibly horrible idols to drive away the bad spirits. Evil spirits are represented in the book of Revelation in the forms of frogs (Rev 16:13). The frogs that the magicians produced could very well have been in the realm of evil spirits. Exactly how the Egyptians thought about this plague is hard to determine, but there is enough evidence to say that the plague would have made them spiritually as well as physically uncomfortable, and that the death of the frogs would have been a “sign” from God about their superstitions and related beliefs. The frog is associated with the god Hapi, and a frog-headed goddess named Heqet was supposed to assist women at childbirth. The plague would have been evidence that Yahweh was controlling their environment and upsetting their beliefs for his own purpose.
3 tn The text literally has “and seven days were filled.” Seven days gave Pharaoh enough time to repent and release Israel. When the week passed, God’s second blow came.
4 tn This is a temporal clause made up of the preposition, the Hiphil infinitive construct of נָכָה (nakhah), הַכּוֹת (hakkot), followed by the subjective genitive YHWH. Here the verb is applied to the true meaning of the plague: Moses struck the water, but the plague was a blow struck by God.