Мидраш к Бамидбар 30:8

(Bamidbar 30:8) "And her husband hear": to exclude one who is deaf. "And her husband hear": This tells me only of his own hearing. Whence do I derive (the same for) others' hearing (and reporting it to him? From (9) "And if on the day of her husband's hearing." (Ibid. 8) "and he be silent to her." He must intend her. If his wife vowed, and he said: "I thought it was my daughter," he may annul it later (see above), it being written "and he be silent to her." He must intend her. "then all of her vows shall stand": If she vowed and he confirmed (her vow by his silence), and he later annulled it, I might think that it is annulled. And how would I understand "then all of her vows shall stand"? If he did not annul them. Or, even if he did annul them, and how would I understand (9) "and he annul her vow"? If he had not confirmed it. Or, even if he did confirm it? (See the same discussion vis-à-vis one's daughter above.) It is, therefore, written "they shall stand," Scripture apprising us that any vow which was confirmed at the time cannot thereafter be annulled.