It is a snare for a person to carelessly declare, “It is holy!”
and then to inquire about it after making his vows. Bible

“inquire about it.” The Hebrew here shows that after making his vows, the man inquires about them, that is, he asks himself and perhaps others about them, and then reconsiders his vows. From God’s perspective, vows are to be made in all seriousness after careful consideration. They are not to be made hastily and then simply undone if they are somehow inconvenient.

Commentary for: Proverbs 20:25