In I Samuel, of the Old Testament, Saul is possessed by an evil spirit, which can be rid of temporarily when David plays the harp. Mr.Rochester says that Jane is better than David when they are reunited. He means that Jane can comfort him completely and that he is dependent on her. She is not dependent on him, which is unusual for a husband and wife at that time. Jane does not marry Mr.Rochester to begin with, because by doing so she would have given up her self to love. One of the reasons she did not marry St. John was because she did not want to be completely under his control. When she is reunited with Mr.Rochester she is equal to him and has kept her self respect.
~Beecham, Robert. "Saul and David" Bible Studies For Growth in God.November 18, 2008. November 30, 2008.