In a day of many and varied denominations, one might wonder what the doctrine and belief of the unified apostolic church looked like. Due to a modern day discovery of an ancient, lost manuscript, now we know. The Demonstration of the Apostolic Preaching is a faithful trasmission of what the intellectual Christian was taught in the second century. Irenaeus, Bishop of Lyons, famed as the subduer of heretics and as the most brilliant Chrisitian mind of his day, now brings us this early body of doctrine, being only decades removed from the apostles of Christ.