Joseph is a pious, finger-pointing pain in the neck. A servant at Wuthering Heights, he seems to resent doing any real work. No one really likes him, but he keeps popping up in the background. He spouts all sorts of religious curses and threats, many of which are hard to understand because of his thick Yorkshire accent. And he makes religion look pretty bad.
He doesn't seem to lead a very compassionate life; he is harsh and self-righteous and his strict judgments about everybody going to hell seem like an unappealing alternative to the mystical beauty of the supernatural to which Catherine and Heathcliff are drawn. His only decency is toward Hareton, and probably only because he knows that Hareton will be master of the Heights someday.