The Vatican II Council spoke at length about Mary, more than any other previous council, and it chose to speak about her in a “Dogmatic Constitution,” the most authoritative sort of text among conciliar documents.
The Council wrote two dogmatic Constitutions
The Council wrote two dogmatic Constitutions: Lumen Gentium, on the Church, and Dei Verbum, on the reading of Sacred Scriptures. Lumen Gentium, the dogmatic Constitution on the Church, was promulgated on November 21, 1964. Lumen Gentium treats of the Church in itself and forms a dyptic with the conciliar document Gaudium et Spes, the pastoral Constitution which treats of the Church in its relationship with the world.
Lumen Gentium contains 8 chapters
Chapter 8 of Lumen Gentium
Chapter 8 appears in continuity, as the summit which illuminates all Lumen Gentium, therefore also the whole Council of Vatican II, of which Lumen Gentium is a key document.