וַיַּעַשׂ יְדֹוָד אֶת הַדָּבָר הַזֶּה מִמָּחֳרָת וַיָּמָת כֹּל מִקְנֵה מִצְרָיִם וּמִמִּקְנֵה בְנֵי יִשְׂרָאֵל לֹא מֵת אֶחָד: וַיִּשְׁלַח פַּרְעֹה וְהִנֵּה לֹא מֵת מִמִּקְנֵה יִשְׂרָאֵל עַד אֶחָד וַיִּכְבַּד לֵב פַּרְעֹה וְלֹא שִׁלַּח אֶת הָעָם:וארא ט:ו-ז
Hashem sent the plague of pestilence which wiped out the livestock of Mitzraim while leaving the animals of Bnei Yisrael untouched. It seems odd then, that the Torah should tell us that Paroh sent out his ervants to see what had happened, and upon hearing that none were killed from among the livestock of Bnei Yisrael, his heart was hardened. Wouldn't hearing that such a thing happened cause the opposite to occur?
This can be explained according to the Malbim who writes that when it says here לא מת ממקנה ישראל עד אחד, it is like when the Torah says of the Mitzrim by the Yam Suf, לא נשאר בהם עד אחד. Chazal explain that Paroh alone survived, meaning that this phrase means "up to but not including this one that survived." Similar language is used in Sefer Shoftim by the battle of Devorah, where we know that Sisra did survive. He writes that here by the Makkah of Dever, if we read it properly according to this understanding, one animal from Bnei Yisrael was killed. It was an animal belonging to the son of a Jewish mother and a Mitzri father. According to Jewish law he was considered a Mitzri in regards to his property. However, when Paroh heard of this he considered the man to be Jewish like his mother. Therefore, in his eyes an animal had died from Bnei Yisrael and Moshe's words had not been fulfilled. According to this is we can better understand why Paroh's heart then hardened.
This can be explained according to the Malbim who writes that when it says here לא מת ממקנה ישראל עד אחד, it is like when the Torah says of the Mitzrim by the Yam Suf, לא נשאר בהם עד אחד. Chazal explain that Paroh alone survived, meaning that this phrase means "up to but not including this one that survived." Similar language is used in Sefer Shoftim by the battle of Devorah, where we know that Sisra did survive. He writes that here by the Makkah of Dever, if we read it properly according to this understanding, one animal from Bnei Yisrael was killed. It was an animal belonging to the son of a Jewish mother and a Mitzri father. According to Jewish law he was considered a Mitzri in regards to his property. However, when Paroh heard of this he considered the man to be Jewish like his mother. Therefore, in his eyes an animal had died from Bnei Yisrael and Moshe's words had not been fulfilled. According to this is we can better understand why Paroh's heart then hardened.
