One of the books I’m reading right now is Gregory Dix’s The Shape of the Liturgy. I’m on page 16 and so far it’s great. Only 736 pages to go!
Something interesting from page 16:
We regard christian worship in general, not excluding the eucharist, as essentially a public activity, in the sense that it ought to be open to all comers, and that the stranger (even the non-christian, though he may not be a communicant) ought to be welcomed and even attracted to be present and to take part. The apostolic and primitive church, on the contrary, regarded all christian worship, and especially the eucharist, as a highly private activity, and rigidly excluded all strangers from taking any part in it whatsoever, and even from from attendance at the eucharist. Christian worship was intensely corporate, but it was not ‘public’.