Ekklesia

From Heim's book, Joseph Ratzinger - Life in the Church and Living Theology, p 347:

Rediscovering Jesus Christ - who gathers his people around himself as ekklesia through their listening to his Word and their celebration of the Eucharist - as the spiritual center of the concept "Church" was, in Ratzinger's view, the chief concern of Lumen gentium. Accordingly, the term ekklesia has a fourfold meaning that expands concentrically: the worshipping assembly, the local community, the Church "in a larger geographical area", and the one Church of Jesus Christ himself. Moreover "there is a continuous transition from one meaning to another, because all of them hang on the christological center that is made concrete in the gathering of believers for the Lord's Supper." [quote from Called to Communion]