Genesis 42:6-7

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

7And Joseph saw his brethren, and he knew them, but made himself strange unto them, and spake roughly with them; and he said unto them, Whence come ye? And they said, From the land of Canaan to buy food.