“And Hashem said to Moshe, ‘Go to Pharaoh for I have hardened his heart and the heart of his servants in order to put My signs in his midst. And in order that you will relate in the ears of your sons and your son’s sons how I made fools of the Egyptians and the signs I put in them. And you will realize that I am Hashem.’ And Moshe and Aharon came before Pharaoh and they said to him, ‘This is what Hashem, the God of the Ivrim, said, “Until when will you refuse to humble yourself before Me. Send out My people and they will serve Me. For if you refuse to send out my people, I will bring locusts in your boundaries.’’’ (Shemos 10, 1-4)”
When Hashem told Moshe to inform Pharaoh that Hashem would be bringing a new makkah (plague), what that makkah would be is not mentioned. It is only written, “And in order that you will relate in the ears of your sons and your son’s sons, how I made fools of the Egyptians and the signs I put in them.” However, when Moshe warned Pharaoh that if he doesn’t send Bnei Yisroel out of Mitzrayim, Hashem will punish him with another makkah—which Moshe then tells Pharaoh will be locusts. If Hashem never told Moshe what the makkah would be, how did Moshe know that it would be locusts?
The midrash (Shemos Rabbah 13:5) explains, “HaKodesh Baruch Hu revealed to Moshe the specific makkah that He was going to bring on Pharaoh, but Moshe only alluded to it in the phrase, ‘in order that you will relate in the ears of your sons and your grandchildren, how I made fools of the Egyptians.’” This is referring to the makkah of locusts—as it is written concerning the makkah of locusts, in the days of Yoel: “Relate to your children about it.”
In other words, the midrash teaches us that Hashem really told Moshe that the coming makkah would be locusts, but Moshe didn’t want to write it openly and only alluded to it with the words: “In order that you will relate in the ears of your sons, how I made fools of the Egyptians.”
The Zera Shimshon asks: What was so unique about the makkah of locusts that it was the only makkah that Moshe only alluded to and didn’t write about it openly?
Secondly, why only in this makkah was it written that the purpose of the makkah was: “… in order to relate it in the ears of your children?” Seemingly, the purpose of all of the makkos was to tell their children how Hashem punished the Mitzriyim for oppressing Bnei Yisroel!
A third question is: Why in pasuk 10, after Hashem struck Mitzrayim with the locusts and Pharaoh agreed that Bnei Yisroel can leave to make their sacrifice, did Pharaoh say, “… realize that evil is opposite you?” Why only after this makkah did he try to frighten Moshe, by saying that something bad is going to happen?
The Zera Shimshon answers these three questions in light of another midrash.
On the pasuk (10:4), “ … for if you refuse to send out my people I will bring locusts in your boundaries.” The midrash explains, “in your boundaries and not in the boundaries of the rest of the descendants of Cham …” From this midrash, we learn a way to establish the exact territory and borders of Mitzrayim; wherever there were locusts, it was Mitzrayim. In a place where there were no locusts, it was not Mitzrayim.
The Zera Shimshon explains the reason why Hashem showed the borders of Mitzrayim—specifically, with this makkah—was because the other makkos did not affect Bnei Yisroel at all. For instance, the water of the Mitzriyim turned into blood, but the water of Bnei Yisroel was unaffected. Bnei Yisroel lived interspersed with the Mitzriyim, so the makkah didn’t fall in the whole territory of Mitzrayim. Wherever one of Bnei Yisroel lived—even though he lived in the middle of Mitzrayim—there was no makkah. Therefore, the makkah did not show the exact boundaries of Mitzrayim.
Concerning locusts, though, it was different. Since some types of locust are kosher, Bnei Yisroel could benefit from them. Hashem, therefore, didn’t want to withhold locusts from them, and locusts also appeared in Jewish neighborhoods and in Jewish homes. True, there were not as many locusts in the dwelling places of Bnei Yisroel as in the rest of Mitzrayim, but still these places were not “locust-free.” Therefore, one could determine the boundaries of Mitzrayim through the locust. Wherever there were locusts—either a lot or a little—was Mitzrayim and wherever there was none, was not Mitzrayim.
Pharaoh didn’t make this distinction between kosher locust and non-kosher locust so from the fact that locust also fell near Bnei Yisroel, Pharaoh understood that Bnei Yisroel also deserved to be punished. He, therefore, told Moshe, “… realize that evil is opposite you.” It wasn’t simply an exaggerated threat, but he really thought that Bnei Yisroel were being punished for their sins just like he was being punished for his sins and Moshe should rethink about taking Bnei Yisroel out of Mitzrayim into the desert.
Since the locusts also appeared to Bnei Yisroel—even though not as a curse—but as something from which they benefited, Moshe didn’t want to mention it by name and only alluded to it.
This is also the explanation why only concerning the makkah of locusts did the Torah write: “And, in order that you will relate in the ears of your sons and your son’s sons, how I made fools of the Egyptians.” Since this was the only makkah that Bnei Yisroel experienced firsthand, it is only concerning this makkah can they, “relate in the ears of your sons and your son’s sons, how I made fools of the Egyptians!”