Genesis 42:8 KJV
And Joseph knew his brethren, but they knew not him.
Genesis 42:8, King James Version
In context
7 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.
8 And Joseph knew his brethren, but they knew not him.
9 And Joseph remembered the dreams which he dreamed of them, and said unto them, Ye are spies; to see the nakedness of the land ye are come.