6 “If she marries after she makes a vow or after her lips utter a rash promise by which she obligates herself

Read Numbers 30:6 Using Other Translations

And if she had at all an husband, when she vowed, or uttered ought out of her lips, wherewith she bound her soul;
"If she marries a husband, while under her vows or any thoughtless utterance of her lips by which she has bound herself,
“Now suppose a young woman makes a vow or binds herself with an impulsive pledge and later marries.