'Swears' in the Bible

"When a man makes a vow to the LORD, or swears an oath an obligation that is binding to himself he is not to break his word. Instead, he is to fulfill whatever promise came out of his mouth.'"

But as for the king, he will rejoice in God. Indeed, everyone who swears by God will exult, because the mouths of liars will be silenced. To the Director: A Davidic Psalm.