Kiddushin 14A

״יבמה יבא עליה ולקחה לו לאשה״. ואימא, לכולה מילתא כאשה! לא סלקא דעתך, דתניא: יכול יהו כסף ושטר גומרים בה, כדרך שהביאה גומרת בה? תלמוד לומר: ״ויבמה״⁠ – ביאה גומרת בה ואין כסף ושטר גומרים בה.

“Her brother-in-law will have sex with her and take her to him as a wife, and perform levirate marriage with her” (Deuteronomy 25:5), which indicates that sex renders her his wife. The Talmud asks: But one can say that with regard to all matters she is like a wife, and therefore she can also be acquired with money or a document like any other woman. The Talmud answers: It could not enter your mind to say this, as it is taught in a baraita: One might have thought that money and a document can complete the acquisition of a yevama and cause her to be married, in the manner that sex completes her acquisition. Therefore, the verse states: “And perform levirate marriage with her” (Deuteronomy 25:5), which indicates that only sex completes her acquisition, but money or a document do not complete her acquisition.

ואימא: מאי ״ויבמה״? דבעל כרחה מיבם. אם כן, לימא קרא: ״ויבם״, מאי ״ויבמה״? שמעת מינה תרתי.

The Talmud asks: But one can say: What is the meaning of: “And perform levirate marriage with her”? It teaches that he can perform levirate marriage without her consent, as unlike an ordinary marriage, a levirate marriage does not require the woman’s agreement. The Talmud answers: If so, let the verse say: And perform levirate marriage, and one would understand that the matter depends entirely on him. What is the meaning of: “And perform levirate marriage with her”? Learn two conclusions from this: First, that a levirate marriage can be performed against her will, and second, that the only way to acquire a yevama is through sex.