Book excerpt: Lumen Gentium, Vatican II's Dogmatic Constitution on the Church, changed how the church thinks about the laity, holiness, baptism, and even the nature and purpose of the church itself. In A Council That Will Never End, the highly regarded ecclesiologist Paul Lakeland marks the fiftieth anniversary of this document's promulgation by taking up three major themes of the constitution, analyzing the text, and identifying some of the questions with which it leaves us. Lakeland is convinced that Lumen Gentium leaves much unfinished business (as any historical document must), that attending to it will take us beyond much of the now sterile ecclesial divisions, and that the ecclesiology of humility it implies marks the way that theology must guide the church in the years ahead.