Gittin 84A

מסתברא, בין לרבי אליעזר בין לרבנן, כיון דפסקה ⁠– פסקה.

It stands to reason, both according to R' Eliezer and according to the Rabbis, that once he separates her, he has separated her entirely. By rendering her entirely permitted for one day he dissolves the bond between them and the divorce takes effect.

תנו רבנן: ״הרי זה גיטיך על מנת שתנשאי לפלוני״⁠ – הרי זו לא תנשא, ואם נשאת ⁠– לא תצא.

§ A baraita states (Tosefta 6:7) that if a man says to his wife: This is your bill of divorce on the condition that you marry so-and-so, she may not marry that man, but if she marries him the marriage is valid and she need not leave her husband.

מאי קאמר? אמר רב נחמן, הכי קאמר: הרי זו לא תנשא לו, שמא יאמרו נשיהן נותנין במתנה. ואם נשאת לאחר ⁠– לא תצא.

The Talmud asks: What is the baraita saying? She is forbidden from marrying whom? Rav Naḥman said that this is what the baraita is saying: She may not marry him, i.e., she may not marry the man mentioned by her husband in the condition, lest people say that these people are giving their wives to each other as a gift. But if she marries another man she need not leave him.

ומשום גזרה ⁠– לא מפקינן מיניה, ושרינן אשת איש לעלמא?!

The Talmud asks: Do we not remove her from him, thereby allowing a married woman to marry anyone, due to a rabbinic decree, lest people say that the husband is giving her as a gift? As long as the condition that she would marry a specific man is not fulfilled, she is a married woman by Torah law.

אלא אמר רב נחמן, הכי קאמר: הרי זו לא תנשא לו, שמא יאמרו נשיהם נותנין במתנה. ואם נשאת לו ⁠– לא תצא, דמשום גזרה לא מפקינן.

Rather, Rav Naḥman said that this is what the baraita is saying: She may not marry him, i.e., the man who was specified in the condition, lest people say that they are giving their wives to each other as a gift. But if she marries him she need not leave him, as we do not remove a woman from her husband due to a decree.