Genesis 42:15-16

15This is how you’ll be tested: I solemnly swear, as surely as Pharaoh lives, that you won’t leave this place unless your youngest brother comes here.

16One of you must be sent to get your brother while the rest of you stay in prison. We’ll see if you’re telling the truth. If not, I solemnly swear, as surely as Pharaoh lives, you are spies!”