The subject of the study is the role of Christianity in a multicultural society. The ongoing discussion on the relationship of Christianity, especially Catholicism in Poland, and national culture, is the justification for this kind of reflection. It is necessary to separate the functions of institutional Church whose task is to accomplish the mission of salvation, regardless of nationality or state. These are Christians who shall participate in broadly understood public life by implementing Christian values in their lives and decisions. This is guaranteed to them by the human rights. The involvement of the institutional Church in public life constitutes a threat for the Church. The Church is universal in nature and, as such, it is not related to any state system. Such understanding of Christianity allowed for its rapid development in ancient Rome.