The article "Lumen Gentium: The Most Important Constitution of Vatican II in Its Sixty Years" by Luiz Cláudio Moraes Correia explores the significance of the Dogmatic Constitution *Lumen Gentium* (*LG*), the most significant document of the Second Vatican Council (1962-1965). *LG*, promulgated on November 21, 1964, by Pope Paul VI, is considered the most important document of the Council, providing a clear definition of the Church and contributing significantly to the understanding of the Church of Christ. The article highlights that *LG* addresses the ecumenical and hierarchical aspects of the Church, emphasizing the Church as the "people of God" and the " Body of Christ." It outlines the Church's nature, mission, and structure, including its visible and invisible dimensions. The document also discusses the role of the Church in the world, its unity with all Christians, and its mission to bring all humanity to salvation. The author notes that *LG* has been a foundational text for numerous theological works over the past 60 years, influencing discussions on the Church's identity and mission. The article concludes by emphasizing the importance of *LG* in understanding the Church's role in the world and in fostering unity among Christians and all people.The article "Lumen Gentium: The Most Important Constitution of Vatican II in Its Sixty Years" by Luiz Cláudio Moraes Correia explores the significance of the Dogmatic Constitution *Lumen Gentium* (*LG*), the most significant document of the Second Vatican Council (1962-1965). *LG*, promulgated on November 21, 1964, by Pope Paul VI, is considered the most important document of the Council, providing a clear definition of the Church and contributing significantly to the understanding of the Church of Christ. The article highlights that *LG* addresses the ecumenical and hierarchical aspects of the Church, emphasizing the Church as the "people of God" and the " Body of Christ." It outlines the Church's nature, mission, and structure, including its visible and invisible dimensions. The document also discusses the role of the Church in the world, its unity with all Christians, and its mission to bring all humanity to salvation. The author notes that *LG* has been a foundational text for numerous theological works over the past 60 years, influencing discussions on the Church's identity and mission. The article concludes by emphasizing the importance of *LG* in understanding the Church's role in the world and in fostering unity among Christians and all people.