Complex sentence: The Roman Catholic Church views that Christ himself established the sacrament of marriage at the wedding feast of Cana; therefore, since it is a divine institution, neither the Church nor state can alter the basic meaning and structure of marriage.
Split into simpler sentences: The Roman Catholic Church views that Christ himself established the sacrament of marriage at the wedding feast of Cana. Therefore, since it is a divine institution, neither the Church nor state can alter the basic meaning and structure of marriage.