Summary: Helpful, but dry, look at history and variety of practice within the Christian Church’s liturgy.
Frank Senn’s Introduction to Christian Liturgy was recommended to me as a good method to understand the historical elements of Christian practice across a variety of traditions. And although a bit dry, it is very helpful. Senn takes different aspects of the liturgy (understood broadly) and breaks them down historically and across denominational lines.
If you every wanted to understand what Baptism is trying to do in a variety of contexts. Or what the order of services are like in Orthodox, Catholic and Evangelical churches. Or what the church year looks like and how the different parts of the sacred year evolved and are celebrated, well this is a good book for that.
This is just an introduction. Whole libraries have been written about the detail and theological minutia. And certainly the historical theology that informs the liturgical development also is just barely scratching the surface. But this is a good introduction and it is widely interested in a fairly full look at the Christian church universal.
I think it was probably written as a seminary textbook and it would be helpful in that context for a first year ministry class. It is still on sale for $7.99 on kindle as part of the Fortress Press sale. Outside of a seminary context, there probably are few that are really interested in this. And as I said, it is a bit on the dull (think lots of overlapping presentations of slight variations of the same thing.)
Introduction to Christian Liturgy by Frank Senn Purchase Links: Paperback, Kindle Edition