Genesis 42:6-7

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