Jaroslav Pelikan - The Christian Tradition: A History of the Development of Doctrine, Vol. 1: The Emergence of the Catholic Tradition (100-600)
I found the above book at the used book store today and purchased it. Any heads up before I try to delve in?
It's been quite a few years since I read it, but fwiw my impressions from what I remember: it's a bit dry but not overly so; it has a good scholarly depth to it; it's probably somewhere between popular level and academic, from what I recall; it covers the bases you'd expect from this period, such as the Christological arguments and such, but it also covers some interesting stuff like how the early writers engaged with (or just dealt with) pagan and pre-Christian beliefs; I'm not sure what group Pelikan was in at the time he wrote it, but I remember the first volume being fairly evenly balanced. Hope you enjoy it!