One question’s answer answers the unresolved question TB Nedarim 73

Today’s daf TB Nedarim 73 tries to answer the question raised on the second half of yesterday’s daf. “Rami bar Ḥama asks: Concerning a husband, what is the halakha with regard to his nullifying a vow without hearing it? In other words, can a husband state a general nullification of his wife’s vows without being aware of any particular vow? When the verse states: “And her husband hears it, on the day that he hears it, and holds his peace at her, then her vows shall be ratified” (Numbers 30:8), is that referring specifically to a situation where he actually heard of a vow, and only then he can nullify it? Or is it not specifically referring to such a situation, and the mention of hearing is merely because the ordinary situation is that the husband nullifies a vow once he hears it?” (Sefaria.org translation)

The Gemara brings two mishnayot and one baraita to support the contention that a husband may nullify vow even without hearing it. Nevertheless, each time the Gemara counters that the sources could be understood in the way that husband says “to her: When I hear the particular vow, then it will be nullified.” (Sefaria.org translation) In other words, we can understand the sources saying that the husband has to hear the in order to dissolve. At this juncture the question remains unresolved. However, the Ron will extrapolate the answer from Rami bar Ḥama’s next question and its answer.

 “Rami bar Ḥama asks: With regard to a deaf man, what is the halakha with regard to his nullifying vows for his wife? If you say that a husband who is not deaf can nullify a vow without hearing it, then perhaps this is because he is capable of hearing. But with regard to a deaf man, who is not capable of hearing, perhaps this is an application of the principle derived from the statement of Rabbi Zeira.

“As Rabbi Zeira said: For any amount of flour suitable for mingling with oil in a meal-offering, mingling is not indispensable for it. Even though it is a mitzva to mingle the flour and oil ab initio, if they were not mingled, the meal-offering is still valid. But for any amount of flour not suitable for mingling, mingling is indispensable for it, and such a meal-offering is invalid. The principle is: Ab initio requirements prevent the fulfillment of a mitzva in situations where they are not merely absent but impossible. In this case, the deaf man does not merely not hear the vow, it is impossible for him to do so.

“Or perhaps the phrase “and her husband hears it” (Numbers 30:8) does not mean that hearing is indispensable to the nullification of a vow, so that even a deaf man can nullify his wife’s vows. Rava said: Come and hear a baraita interpreting that verse: “And her husband hears it”; this excludes the wife of a deaf man. The Gemara concludes: Learn from this baraita that a deaf man cannot nullify his wife’s vows.”(Sefaria.org translation)

The conclusion of the Gemara is the verse ““and her husband hears it” (Numbers 30:8)” only excludes the deaf husband. The ability to hear is a crucial component of the husband’s ability to annul a vow The Ron ד"ה בָּעֵי רָמֵי בַּר חָמָא: חֵרֵשׁ, מַהוּ שֶׁיָּפֵר לְאִשְׁתּוֹ citing Ramban writes only the deaf husband cannot dissolve his wife’s vows because he cannot hear. Regular people who can hear may dissolve the wife’s vow even without hearing it based on Rabbi Zeira’s principle. As long as the potential to observe the mitzvah (in this case the ability to hear), the mitzvah is accomplished even not performed ab initio (in this case the husband has the ability to dissolve his wife’s vow even without hearing it).