Genesis 42:12-16 New King James Version (NKJV)

12. But he said to them, “No, but you have come to see the nakedness of the land.”

13. And they said, “Your servants are twelve brothers, the sons of one man in the land of Canaan; and in fact, the youngest is with our father today, and one is no more.”

14. But Joseph said to them, “It is as I spoke to you, saying, ‘You are spies!’

15. In this manner you shall be tested: By the life of Pharaoh, you shall not leave this place unless your youngest brother comes here.

16. Send one of you, and let him bring your brother; and you shall be kept in prison, that your words may be tested to see whether there is any truth in you; or else, by the life of Pharaoh, surely you are spies!”

Genesis 42