Genesis 42:13-17

But they said, “Your servants are twelve brothers in all, the sons of one man in the land of Canaan; and behold, the youngest is with our father today, and one is no longer alive.”

Yet Joseph said to them, “It is as I said to you, you are spies;

by this you will be tested: by the life of Pharaoh, you shall not leave this place unless your youngest brother comes here!

Send one of you and have him get your brother, while you remain confined, so that your words may be tested, whether there is truth in you. But if not, by the life of Pharaoh, you are certainly spies!”

So he put them all together in prison for three days.