Numbers 24:8

24:8 God brought them out of Egypt.

They have, as it were, the strength of a young bull;

they will devour hostile people

and will break their bones

and will pierce them through with arrows.

Numbers 30:2

30:2 If a man makes a vow to the Lord or takes an oath of binding obligation on himself, he must not break his word, but must do whatever he has promised.