Amalek's fall opens conversion to the nations

בפסוק ורבים מעמי הארץ מתיהדים כי נפל פחד היהודים עליהם.

On the verse: "And many of the people of the land became Jews (misyahadim), for the fear of the Yehudim had fallen upon them" (Esther 8:17).

The Sefas Emes opens with the verse describing the wave of conversions after the Purim miracle, prompted by a "fear of the Yehudim."

ולכאורה קשה כי לא באו בני ישראל להלחם רק עם הקמים עליהם לרעה ומה פחד הי' להם להתגייר עי״ז.

At first glance this is difficult: for Bnei Yisrael came to fight only against those who rose up against them for evil — so what fear was there for these others that should make them convert because of it?

The Jews only struck their actual enemies, so the nations not involved had no reason to fear for their lives; why then would fear drive them specifically to become geirim?

ויתכן לפרש כי עליהם חוזר על עמלקים.

It is possible to explain that "upon them" refers back to the Amalekites.

The Sefas Emes suggests that "the fear of the Yehudim fell upon them" means upon Amalek, not upon the converts themselves.

כת המן הרשע.

The faction of Haman the wicked.

"Them" denotes Haman's Amalekite party, the enemies who were defeated.

שהם המכסים את הפנים ולכן הם מונעים לבני עולם להתגייר ולכנוס תחת כנפי השכינה.

For they are the ones who cover the Face (of holiness), and therefore they prevent the people of the world from converting and entering beneath the wings of the Shechinah.

Amalek's spiritual function is to conceal the revelation of Hashem in the world; this concealment is precisely what blocks the nations from being drawn to convert and shelter under the Divine Presence.

וכיון שנפל פחד היהודים עליהם.

And since the fear of the Yehudim fell upon them (the Amalekites).

Once Amalek — the force of concealment — was broken and gripped by fear, its power to hide the truth collapsed.

ניתוספו גרים בישראל כנ״ל.

Converts were added to Yisrael, as above.

With the concealing power of Amalek shattered, the hidden light of Hashem could shine, and the nations were now free to be drawn toward conversion.

ועם זה מיושב מה שדקדקו המפרשים למה קיבלו גרים מבני עמלק עיין בס' מנות הלוי ולפמ״ש עמי הארץ לא קאי על העמלקים:

And with this is resolved the difficulty the commentators raised — why converts were accepted from the descendants of Amalek; see the sefer Manos HaLevi — for according to what we have said, "the people of the land" does not refer to the Amalekites.

The commentators were troubled that Jews accepted converts from Amalek, whose seed we are commanded to wipe out. But on this reading, the "people of the land" who converted were other nations, not Amalek; Amalek is merely the "them" upon whom fear fell, so the difficulty dissolves.

Summary: The Sefas Emes resolves a difficulty in the Purim verse by reading "the fear of the Yehudim fell upon them" as referring to Amalek, Haman's faction, rather than to the converts. Amalek's spiritual role is to "cover the Face," concealing the revelation of Hashem and thereby preventing the nations from converting and entering beneath the wings of the Shechinah. When Amalek's power was broken at Purim, that concealment lifted and many nations were drawn to become geirim. This also answers the commentators' question of how converts could be accepted from Amalek: "the people of the land" who converted were other nations, not Amalek itself.