Bible Verses About Oaths: Custom of swearing by the life of the king

And this is how you will be tested: As surely as Pharaoh lives, you shall not leave this place unless your youngest brother comes here.

Send one of your number to get your brother; the rest of you will be confined so that the truth of your words may be tested. If they are untrue, then as surely as Pharaoh lives, you are spies!”