Hindley begins to treat Heathcliff abominably - "his treatment of (Heathcliff) (is) enough to make a fiend of a saint". Hindley takes from Heathcliff the opportunity to continue "his early education", subjecting him instead to "continual hard work, begun soon and concluded late". Heathcliff responds by appearing "delighted to witness Hindley degrading himself past redemption, and (becomes) daily more notable for savage sullenness and ferocity".
Heathcliff's relationship with Catherine is directly affected by Hindley's actions towards him. Because he is no longer allowed to pursue his studies, "his childhood's sense of superiority...(is) faded away", and although "he struggle(s) long to keep up an equality with Catherine in her studies", he eventually must give up the endeavor. His "personal appearance sympathize(s) with (his) mental deterioration"...and he acquire(s) a slouching gait and ignoble look"; Heathcliff's whole demeanor descends into one of "unsociable moroseness". Displeased by Heathcliff's deterioration, Catherine begins to scorn him, and to prefer the company of the more cultured Edgar Linton (Chapter 8).