Numbers 30:2

2 if a man makes a vow for Yahweh or swears an oath with a binding pledge on himself, he must not render his word invalid; he must do all that went out from his mouth.

Numbers 30:2 In-Context

1 Then Moses spoke to {the leaders} of the tribes concerning the {Israelites}, saying, "This [is] the word that Yahweh commanded:
2 if a man makes a vow for Yahweh or swears an oath with a binding pledge on himself, he must not render his word invalid; he must do all that went out from his mouth.
3 "If a woman makes a vow to Yahweh, and she binds a pledge [on herself] in her father's house in your childhood,
4 but if her father hears her vow or her pledge that she bound on herself and says nothing to her, then all her vows will stand, and every pledge that she binds on her life will stand.
5 If her father forbids her on the day he hears [of it], all her vows or her pledges that she bound on herself will not stand, and Yahweh will forgive her because her father has forgiven her.
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