Gold  is synonymous with money in the novel.   William Dane’s theft of the money in the church disengages the  relationship between Silas and him.  It  is the loss of gold and betrayal of their friendship that leads to Silas lost  of faith in the church, and makes him distant himself from the people.  Silas’ money eventually turns out to be his  companion while he isolates himself from the people.  It is also the loss of his money that leads  him back to the people and eventually he regains his faith.
                    This  question was fairly attempted by the candidates.