I don't know why no one has ever brought it up before. I assume at least a handful of people have made themselves acquainted with all of our earliest sources about this sect. I must assume that one of the reasons no one has ever published something on this, is that promoting the idea that the Marcionites thought Marcion was an apostle - if not the apostle - has the effect of making one look rather silly. Whatever the case may be, here is the chief evidence:
1. Instead of Peter they (the Marcionites) set up for themselves Marcion as the head of the apostles [Marutha of Meparkat, Mesopotamia]
2. And that of the apostles, embracing the ministry of Paul, ends with Nero. It was later, in the times of Adrian the king, that those who invented the heresies arose ... Marcion, who arose in the same age with them (the apostles), lived as an old man with the younger. After him Simon heard for a little the preaching of Peter. [Clement of Alexandria]
3. if Marcion be an apostle (as they claim), nevertheless as Paul says, "Whether it be I or they, so we preach" [Tertullian of Carthage]
We shall develop this understanding even further, but let us start with the jarring conclusion that the Marcionites are reported to have believed Marcion was an apostle - if not 'the apostle' - and move on from there in subsequent posts.
