Genesis 42:6-9

6And Joseph was the governor over the land, and he it was that sold to all the people of the land: and Joseph’s brethren came, and bowed themselves before him with their faces to the earth.

7And Joseph saw his brethren, and he knew them, but made himself strange to them, and spoke roughly to them; and he said to them, Where do you come from? And they said, From the land of Canaan to buy food.1 8And Joseph knew his brethren, but they knew not him. 9And Joseph remembered the dreams which he dreamed of them, and said to them, Ye are spies; to see the nakedness of the land have ye come.