I'm thinking about how like kings how they would trace their lineage back to see who is closest related to the original king. I'm thinking has the Orthodox Church's doctrines remained pure to the early church? Is she (the Orthodox Church) the closest in the world to the early church? I'm thinking that the only real other contender would be the Catholic Church; seeing as all the Protestant churches were founded in the 1500's. I know that liturgy was used in the early church and is still used.
Would a good way to do this be to read the book of Acts? And the other books in the Bible that are about the early church?
I hope that is clearer.
It is. Thank you.
Firstly, though, I would make a note about the "Early Church." I hear this from people a lot, actually, both Orthodox and not. The Orthodox, who are usually converts (as I myself am) start talking about how we're the "early church" and likewise those who aren't Orthodox always talk about "getting back to" the early church. I think both of these are somewhat flawed. Orthodoxy is not the Early Church, nor is it "like" the Early Church. It is the exact SAME Church which is eternal. We have a living tradition that changes in expression, though never in doctrine. Going back to the "old" ways of doing things (i.e., anachronism) is not the way to find Truth. In the same way, the non-Orthodox who want to "get back" make the mistake of trying to take a snapshot of the Church, when it's really a video. If we believe the body of Christ is alive and active, snapshots will only capture parts of it (and even then, parts that have changed over time will be different or missing). The doctrine stays the same, the exteriors change with time.
That said, it seems you're looking for validation that all things which are taught by the Orthodox Church today were doctrines from the beginning. That can be reviewed and seen, it's an historical study of the Church. It's this approach that really appealed to me as a convert, and I found it by talking about the Scriptures with knowledgeable Orthodox Christians who could explain a passage properly and then point to centuries of Church Fathers who have said the same over and over again.
Eventually, I saw this Deposit of Faith transversing history from Christ until the present, and that it was that which is maintained in the Orthodox Church. I came to this by a lot of reading and talking with people over a decent period of time (about a year). I tackled different issues as I thought of them and heard what the Orthodox say, the Catholics say and then what various Protestants say and weighed it against what I found being said throughout history by Christians. Orthodoxy seemed to be the one that was always consistent on all points, and everyone else varied on some issue(s) when compared to the historical account of the Christian Faith as seen in the Fathers.
I know that doesn't really refer you to anything, just gives you a broad approach. It's time-consuming and sometimes down right annoying to track some of this stuff down. But, it was worth it to me. I learned a lot about the history of Christianity, and it reshaped my entire understanding of the Faith (I did become Orthodox, after all) and I'm still finding new things. I imagine that I always will be.