Presumably, the Egyptians closed their windows and doors to keep the hordes of locusts out of their homes. How then did the locusts fill the houses?
Oznayim la'Torah: This was a proof that this was not a natural plague of locusts, 1 but the work of Ha'Kadosh-Baruch-Hu.
Why did Moshe and Aharon opt to take their leave of Pharaoh without his consent?
Ramban #1: Moshe saw how frightened they became by the plague of hail, and he figured that the warning on locusts that would destroy every vestige of food that was left would have a similar effect. So he left on the presumption 1 that they would discuss the matter and hopefully would end up doing Teshuvah. 2
Ramban #2: In fact, Moshe acted in the same way by all the plagues - warning them and leaving the room. And the Torah only mentions it here because Pharaoh called them back. 3
What are the implications of "va'Yifen va'Yeitzei mi'Im Pharaoh"? Why does the Torah mention it only here?
Oznayim la'Torah: There is a difference of opinion as to whether Moshe turned to face Pharaoh in the respectful manner that one takes leave of a king, or whether he turned round and left with his back to Pharaoh. And the Torah mentions it specifically here because it is the only time that it records what Moshe said to Pharaoh in his palace. 1
Oznayim la'Torah: He also warned him in the palace prior to Tzefarde'a and Dever, but the Torah does not record what he said to him.
