The Apocalypse of Peter is unique because of the Muratorian fragment. That fragment dated to about 170 AD is frequently cited as evidence that our current Canon was basically agreed upon very early. However a few books in our current canon aren't mentioned (James, and both of Peter's Epistles are absent and it seemingly knows only two of John's). And it approves of three books not in our current Canon, though one of those is explicitly said not to be Scripture just that it isn't objectionable, the Shepherd of Hermas. It mentions The Wisdom of Solomon, which seems odd to be mentioned here since it would be Old Testament if it was Canon (it might be included as a reference point for how Paul uses it in Romans with the purpose of refuting it). And lastly it defines as inspired Scripture the Apocalypse of Peter, yet strangely says how some think it shouldn't be read in Church. According to Eusebius, Clement of Alexandria also considered the Apocalypse of Peter canon.
The Apocalypse of Peter is preserved for us in two versions, a Greek Text found in Egypt, Akhmim specifically, and the Ethiopian version. The translation Bart Ehrman included in his Lost Scriptures book is based on the Akhmim text, and in a 30 minute lecture on the book on YouTube he acts like only that version exists, claiming the book was lost until that manuscript was found when in fact the Ethiopian version was already well known even to Western scholars. So be aware that Ehrman doesn't provide all the information.
Now I think I'd already said in a prior post how the Apocalypse of Peter supports the interpretation that the Fig Tree of Matthew 24 represents Israel.
The Ethiopic version contains a passage that explicitly promises the eventual Salvation of all Sinners.
"My Father will give unto them all the life, the glory, and the kingdom that passeth not away, ... It is because of them that have believed in me that I am come. It is also because of them that have believed in me, that, at their word, I shall have pity on men... "There are a few reasons why I think this was in the original version and not something added on the way to Aksum.
First of all that the surrounding context of this promise includes statements that it should be kept a secret from Sinners is the best explanation for why the Muratorian fragment says some felt it shouldn't be read in Church. This attitude (also held by Origen a student of Clement) is part of why I don't support adding this book to the Canon, I disagree with it as a modern Evangelical Universalist. Maybe it made some practical sense in the circumstances of 2nd/3rd century Egypt, but today the perception that God is a Wrathful monster who tortures people without end is purely an obstacle to The Gospel.
M.R. James who made the 1924 Translation for The Apocryphal New Testament expresses the opinion that the Ahkmim text isn't the proper Apocalypse of Peter at all but an Abridged version written to be included in a Gospel of Peter as it's Olivte Discourse. The promise of Universal Salvation may have been removed for the above stated reason.
The Christian Sibylline Oracles which were influenced by the Apocalypse of Peter also includes an equivalent promise.
And then lastly if we view it as God's Word, the Ethiopian version is the received text, so like my reasons for choosing the Textus Receptus Greek Text for the canonical New Testament, and why many Aramaic primacy supporters favor the Peshita over the Sinai Gospels, the true version must be the one The Holy Spirit preserved, not something buried and forgotten for millennia.
Meanwhile the Ahkmim version still doesn't contradict the promise of Universal Salvation. Chances are the word translated Eternal is Aionion/Aionios, but even if not I could still argue it to be compatible. At face value what's said in chapter 13 of Ehrman's version might seem to rule out Universal Salvation, but that scene happens in the Ethiopian version as well, then later on Peter pleads for them. That passage says they won't get released before their sentence is up based on their own repentance, just like a modern Prison sentence. But eventually it will be the Believers having mercy on them that will trigger their release.
If I were to view this text as Scripture, how would I deal with any apparent contradictions to other Scripture? Well first of all I see it being framed in a parable like fashion, so the details need not be something we build doctrine on, (like with the Lazarus and the Rich Man in Luke 16), but is rather making the point that the punishments will fit the crime. I certainly don't think it intends to say it's a Sin for Women to braid their hair, that sequence is probably meant to be about Prostitution, though I don't know whether or not the word Porneia was used where English translations often say Fornication.
However I still do not view it as Scripture. But that it was pretty popular with the Early Church shows that Universal Salvation was not something they had a problem with. And I can build the Doctrine of Universal Salvation using John's Apocalypse.
