What's the meaning of the quote? “He looked in astonishment, no longer at himself, but at an awesome stranger.” ( Chapter 4 pg. 63)

In this quote, Golding informs the reader that Jack is no longer Jack.... no longer himself. Jack has become a complete stranger.... to everyone, inclusing himself. The face paint... the mask, has unleashed Jack's base instincts. He is no longer held back by shame, morality, ot guilt. From this point forward, Jack embraces the barbarity and uses it to claim leadership over the other boys.