There's an oft-repeated (and also apocryphal) quote from an old lady who was defending why she still used the King James version of the Bible. Her explanation? "If it was good enough for Jesus, it's good enough for me."
When it comes to matters of faith for Christians who are of a relatively newer historical variety - such as evangelicals - sometimes it's easiest to forget about historical context and just assume that one's own experience must have been the same for all "true" Christians across all eras and cultures. This is especially true for evangelicals when it comes to the Bible, and for obvious reasons. The cry of "Sola Scriptura" provides the bedrock for much of the evangelical identity, and if the Bible in its English-language form is so important to Christians today, wouldn't it also have had the same importance for Christians in the first few centuries of the movement?
The reality of the Bible is more complex, however. For example, the earliest definitive list of all 27 books that make up the New Testament did not show up on the historical record until 367 AD, and it was not until church councils in 393 and 397 that leaders of the Church officially confirmed the list of New Testament books that we have today.
In the meantime, Christians in the first few hundred years of the Church's existence had a variety of ideas about what books were Scripture and what were not (this website provides an excellent chart of the various "canons" held by individual Christians throughout those years). Some books, such as many Pauline epistles and the four gospels, were pretty much universally recognized as Scripture from an early date. Other books, such as 2 John, 3 John, and Revelation, were the subject of debate as to their legitimacy. Still other books, such as the Epistle of Barnabus, 1 Clement, and the Shepherd of Hermas, were considered to be Scripture by some Christians (but not all) before eventually losing favor and being kept out of the Christian canon.
That such debates existed in the Church can be a bit jarring to Christians who may have operated under the assumption that the Bible existed in its present form for the Church's entire history. Yet, thoughtful Christians of all varieties over the centuries have been well aware of how the Bible came into its present form, and have not found that historical reality contradicts their belief in the authority of Christian Scripture (For an easy-to-read evangelical explanation of the historical development of Scripture, you can check out p. 57-66 of Bruce Shelley's Church History in Plain Language...and no matter what variety of Christianity you espouse, including the variety that says Christianity is bunk, you can find a historian who can fit the history into your worldview).
I've always been fascinated by those books that were considered important to the early church, but didn't quite make the cut into Christian Scripture. I've read through English translations of most of those borderline books, and found that, in every case, I'm thankful that the book didn't get into the Bible. Thus, as the first in a series that I may or may not decide to continue, depending on my whims, I decided to give a quick overview of why Christians should be thankful that those books did not make the canon: first up, the Shepherd of Hermas!
Here's why, if you are a Christian, you should be happy that the book didn't make the cut:
According to Hermas, you are allowed exactly one sin after you have been baptized. If you commit more than one post-baptismal sin, you cannot be saved. Apparently, an early debate in the church revolved around the nature of continued sin after baptism. It was believed that at the time of baptism, all previous sins were forgiven, and a person could then gain entrance into heaven.
However, that did not resolve the question of new sins. In the words of the author of Hermas, "Certain teachers [say] that there is no repentance beyond what occurred when we descended into the water and received the forgiveness of our previous sin." Other teachers apparently suggested that one could receive repentance for multiple sins committed after baptism. In Hermas, the issue was resolved with a compromise of sorts. An angel reportedly told the author that a person who has received baptism "has one opportunity for repentance" but that any more than one "makes repentance useless."
To modern eyes, Hermas seems to be a bit harsh, not to mention arbitrary. Yet, for some early Church fathers, including Tertullian (who supposedly coined the term "Trinity"), its allowance for one post-baptismal sin was too lax. Tertullian originally considered the book to be part of Scripture, but later rejected it because of the repentance issue. Church leaders in future centuries also rejected the book as Scripture, although for different reasons. And thank God they did.
(For an excellent overview of early non-canonical Christian writings, I recommend The Apostolic Fathers in English edited by Michael W. Holmes)