Commentaire sur Les Nombres 30:15

מיום אל יום [BUT IF HER HUSBAND ALTOGETHER HOLD HIS PEACE AT HER] FROM DAY TO DAY — In order that you should not say that ביום שמעו in v. 13 means that the husband has the right of annulling from the time on the day when she made the vow to the same time on the next day (i.e., twenty-four hours), it accordingly states מיום אל יום, i.e., from the day when she makes the vow up to the next day, — to tell you that he may annul the vow only up to when it becomes dark, [for then another day begins] (cf. Nedarim 76b).

ואם החרש יחריש, when someone who has the authority to cancel a vow keeps silent when he hears it, it is as if he had given his consent by not voicing his objection.

So that you should not say [he may annul] for twenty-four hours. Rashi wishes to answer the question: Why is it necessary to write, “From one day to the next”? We cannot say it comes to teach that if he did not annul it on the day he heard, he can no longer annul it. For the Torah had already written (v. 8), “And her husband heard about them and remained silent on the day he heard, then [her vows] shall stand.” Rashi answers that if it had not written, “From one day to the next” one might have said that previously when it wrote, “On the day he heard” this was [measured] from "moment to moment," namely a twenty-four hour period.

V. 15. ואם החרש יחריש לה, selbst בשותק על מנת למיקט (Nedarim 79a). selbst wenn er nicht in der Absicht geschwiegen, das Gelübde aufrecht zu halten, sondern nur, um die Frau eine Zeit lang in der Schwebe zu lassen und dann Einsprache zu tun, ist mit Sonnenuntergang, und Ende des Tages, an welchem er von dem Gelübde gehört, die Einsprache nicht weiter möglich. Ein Schweigen in zustimmender Absicht gibt dem Gelübde sofort Bestand und kann selbst an demselben Tage keine Einsprache mehr geschehen קיים בלבו קיים (daselbst).

Until nightfall. Meaning that if he heard during the day, even if it was close to sunset, once he remained silent until nightfall he can no longer annul.