Hassidout sur L’Exode 8:7

And according to what was said [above], we can aim to understand that which is found in the Midrash: That He sent [word] to him five times, and he did not pay any attention to His words — the Holy One, blessed be He, saying to him, "You have stiffened your neck and you have hardened your heart." As it calculates the five times that the expression of hardening the heart is used: After the wonder of the snake, it is written: Pharaoh’s heart is hard (Exodus 7:14). After the plague of the frogs, it is written: he hardened his heart (Exodus 8:7). After the plague of the mixture of wild animals, it is written: And Pharaoh hardened his heart (Exodus 8:28). After the plague of pestilence, it is written: And the heart of Pharaoh remained hard (Exodus 9:7). And after the plague of hail, it is written: and he hardened his heart, etc. (Exodus 9:34). So since he hardened his own heart and made it impenetrable, this punishment came to him, that the Holy One, blessed be He, [also] hardened his heart and made it impenetrable, as is mentioned above. However, any expression of strengthening of the heart that is written is not counted here. As that is not at all from the same idea as hardening the heart, such that it would not be measure for measure.

And the Lord did according to Moses' word; the frogs died away, from the houses, from the courtyards, and from the fields: Meaning, that since the Holy One, blessed be He, desired to fulfill the word of His servant and the faithful prophet to His [people], Moses, they therefore died in this order, first from the houses, afterward from the courtyards, and afterward from the fields. For Pharaoh's request was like this, since he said, that He may remove the frogs from me, and from my people (Exodus 8:4), meaning first from me and afterward from my people, that the removal be in order of the closest first. And likewise did Moses promise him and say, the frogs shall depart from you and your servants [and your people], etc. (Exodus 8:7). And hence in order to fulfill Moses' word, He did so: the frogs died away, from the houses, from the courtyards, etc.. This would not have been so had the Holy One, blessed be He, brought them back to the Nile. It would not have been in this order. For the closer ones would return to the Nile first, and those are the ones from the fields, and afterwards the ones from the houses. And even though Moses said to Pharaoh, only in the Nile shall they remain, its understanding is not that they would return to the Nile, but rather that they would all die. And the only ones that would remain are the ones that had stayed in the Nile, like the statement of the sages, may their memory be blessed (Shemot Rabbah 10:5). And the Holy One, blessed be He, did it to sanctify His great and holy name — that nothing should be missing from that which Moses said, and they would trust the Lord and Moses His servant (alluding to Exodus 14:31).