TT #708 · Parashas Ki Seitzei · Seventh Aliyah · Passuk 25:07
And if the man does not desire to take his yevamah, then his yevamah shall go up to the gate to the elders and say: “My husband’s brother refuses to establish a name for his brother in Israel; he will not perform the duty of a husband’s brother for me.”
Torah Temimah points to Yevamot / Sifrei.
TT lemma: וְאָמְרָה.
וְאָמְרָה – מִלַּמֵּד שֶׁהִיא צְרִיכָה לוֹמַר אֶת הַדְּבָרִים בִּלְשׁוֹן הַקֹּדֶשׁ, אוֹ עַל כָּל פָּנִים בְּשָׂפָה שֶׁהַדַּיָּנִים מְבִינִים.
English: “And she shall say” — teaching that she must pronounce the declaration (preferably in the holy tongue, or at least in a language the judges understand).
On the daf / in context: The verbal declaration is an essential component of the chalitzah rite.
Derash on the necessity of the spoken formula.
The yevamah must recite the prescribed declaration as part of the chalitzah ceremony.