John Gill Commentary Numbers 30:14

"But if her husband altogether hold his peace at her from day to day, then he establisheth all her vows, or all her bonds, which are upon her: he hath established them, because he held his peace at her in the day that he heard them." — Numbers 30:14 (ASV)

But if her husband altogether hold his peace at her from day
today
Said not one word to her day after day, neither on the day he heard her vow, nor the day following:

then he establishes all her vows, or all her bonds, which are upon
her ;
by his silence:

he confirms them, because he held his peace at her, in the day that
he heard them ;
for not to contradict them was to confirm them.