The analysis covers the main determinants of the legal doctrine of the Roman Catholic Church that pertain to the dignity and greatness of matrimonial vocation and the Catholic family. They are: a) establishment of a deep communion of the married couple and family life on the sacrament (i.e. covenant); b) the generous procreation and upbringing of children in the Roman Catholic faith. They are based on the incorporation of this family into the same Church, as well as on respecting her laws, which integrates the community of faith on the way to salvation. Hence, the 1983 Code of Canon Law contains a system of requirements (i.e. the so-called obstacles, as well as powers or indications) to protect marriage and exclude situations in which the interest of the Catholic faith or of prospective spouses would be threatened.