I cannot recommend this book highly enough. Modern Christians don't know nearly enough about the history of the Church (aside from 'the Apostles died and everyone apostatized until Luther'), and so this overview of the first centuries of the Church's sojourn is very welcome.
This is not a dry and academic book, and it doesn't bog down in the swamp of information and dates that some works do. It doesn't pretend to be anything other than a survey of the early years, and even takes the time to warn in particular that history is rarely so neat and straightforward. Nonetheless, it does an excellent and very readable job of moving through the early years of the Church, pointing out early controversies and their solutions, introducing us to the Saints as real people, with real lives and stories, walking us through Ecumenical Councils, the Desert Fathers, and the formation of the canon that today we call the New Testament.
To be clear, this is not the history of A church, this is the history of THE Church. The idea of multiple Churches was unheard of (and should be still). All groups that today call themselves Christian share this history and trust those who walked the path with such basic things as defining which books to call Scripture - and the canon came later!
If you're interested in early Christianity or are just trying to find that original 'strain', this is the book for you. Read it, then stop by a local Orthodox Church and live it. But at the very least dive in and read, and learn about the history of the Christian Faith.