But if her husband prohibits her when he hears of it, he nullifies the vow that binds her or the rash promise she has made, and the LORD will absolve her.

Leviticus 5:4
Or if someone swears thoughtlessly with his lips to do anything good or evil--in whatever matter a man may rashly pronounce an oath--even if he is unaware of it, when he realizes it, he is guilty in the matter.

Numbers 30:5
But if her father prohibits her on the day he hears about it, then none of the vows or pledges by which she has bound herself shall stand. The LORD will absolve her because her father has prohibited her.

Numbers 30:7
and her husband hears of it but says nothing to her on that day, then the vows or pledges by which she has bound herself shall stand.

Numbers 30:9
Every vow a widow or divorced woman pledges to fulfill is binding on her.

But if her husband disallowed her on the day that he heard it; then he shall make her vow which she vowed, and that which she uttered with her lips, with which she bound her soul, of none effect: and the LORD shall forgive her.