SUMMARY: The article has two parts. Firstly, there is an outline of the historical journey which led the formulation of number five, dedicated to the Kingdom of God, in the Dogmatic Consti­tution on the Church Lumen Gentium. The troubled «iter» of the Conciliar Document, until it rea­ched its definitive draft, demonstrates how difficult it may have been to overcome the misunder­standing of the past (either a strict link or a clean break between the Church and the Kingdom of God) and so bring back a proper balance between the two realities (the identity in the difference). Secondly, the author evaluates the theological significance of number five of «Lumen Gentium». This reading sets the relationship between the Curch and the Kingdom of God against a symbo­lic-sacramental background: the Church sacrament and icon of the Kingdom of God.