Cross reference
Genesis 42:33
33 The man, the lord of the land, said to us, 'Hereby will I know that you are honest men. Leave one of your brothers with me, and take grain for the famine of your houses, and go your way.
Genesis 42:19-20
19 If you are honest men, then let one of your brothers be bound in your prison-house; but you go, carry grain for the famine of your houses.
20 Bring your youngest brother to me; so will your words be verified, and you won't die." They did so.
Genesis 42:15
15 Hereby you shall be tested. By the life of Pharaoh you shall not go forth from here, unless your youngest brother come here.