I just finished this book by Bart Ehrman and liked it very much.
The book provides an introduction on many topics regarding early Christianity that shaped what we have come to understand as Christianity and its canon and core beliefs.
There is a discussion on "Scripture" that did not become part of the mainstream canon and how we ended up with this canon in the first place. In addition there is a summary of three main groups of early Christianity that lost out for the most part - Ebionites, Marcionites and Gnostics (actually this last was quite diverse). There is also an explanation of how the "war" was fought and how the winners "won". This includes likely forgery and alteration - even in canonical books!
Lots of good information for people just getting started on these topics. Note that this book focuses on issues BEFORE the issues with the Trinity like Arianism and all that heated up, although there is some mention of this.
Recommended. Let me know what you think.
