Old lights and new lights preachers both followed protestantism. how did the two differ? old lights preachers believed religion should be practiced in a rational way while new lights preachers propagated emotion in religion. old lights preachers believed in salvation through god’s grace while new lights preachers believed in salvation through charity. old lights preachers restricted membership to their churches while new lights preachers welcomed all into their churches. old lights preachers attempted to rationalize the dictates of the church of england while new lights preachers tried to revive puritanism. old lights preachers encouraged looking at religion through science while new lights preachers separated science from religion.