Genesis 42:16-19

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!”

17Then he put them in jail for three days.

18On the third day Joseph said to them, “Do this, and you will live. I, too, fear God.

19If you are honest men, you will let one of your brothers stay here in prison. The rest of you will go and take grain back to your starving families.