Another interpretation: "And He shone forth from Seir upon them" (Deuteronomy 33:2). When the Holy One, blessed be He, stands to exact punishment from Seir, He will in the future shake the whole world over its inhabitants in the same way that He shook it at the giving of the Torah, as it is said (Judges 5:4): "O LORD, when You went forth from Seir, when You marched from the field of Edom, the earth trembled, the heavens also dropped, the clouds also dropped water." And it says (Genesis 25:26): "And afterward his brother came out, and his hand was grasping the heel of Esau, and his name was called Jacob." The Holy One, blessed be He, said to them: No nation or tongue shall enter in between you.
When God Thundered at Sinai the Whole World Trembled
Sifrei Devarim 343:7
דָּבָר אַחֵר, וְזָרַח מִשֵּׂעִיר לָמוֹ, כְּשֶׁעוֹמֵד הַקָּדוֹשׁ בָּרוּךְ הוּא לִפָּרַע מִשֵּׂעִיר עָתִיד לְהַרְעִישׁ אֶת הָעוֹלָם כֻּלּוֹ עַל יוֹשְׁבָיו כְּדֶרֶךְ שֶׁהִרְעִישׁ בְּמַתַּן תּוֹרָה, שֶׁנֶּאֱמַר (שופטים ה ד): ״ה׳ בְּצֵאתְךָ מִשֵּׂעִיר בְּצַעְדְּךָ מִשְּׂדֵה אֱדוֹם אֶרֶץ רָעָשָׁה גַּם שָׁמַיִם נָטָפוּ גַּם שְׁחָקִים יִזְּלוּ מָיִם״, וְאוֹמֵר (בראשית כה כו): ״וְאַחֲרֵי כֵן יָצָא אָחִיו וְיָדוֹ אוֹחֶזֶת בַּעֲקֵב עֵשָׂו וַיִּקְרָא שְׁמוֹ יַעֲקֹב״. אָמַר לָהֶם הַקָּדוֹשׁ בָּרוּךְ הוּא: אֵין כָּל אֻמָּה וְלָשׁוֹן נִכְנֶסֶת בֵּינֵיכֶם.