Genesis 42:18-20

And the third day he brought them out of prison, and said: Do as I have said, and you shall live: for I fear God.

If you be peaceable men, let one of your brethren be bound in prison: and go ye your ways, and carry the corn that you have bought, unto your houses.

And bring your youngest brother to me, that I may find your words to be true, and you may not die. They did as he had said.