Meanwhile, whatever possessions your god has, ought to have come into view at the same time as the god whose they are. Yet how is it that their owner has been in evidence since the fifteenth year of Tiberius Caesar, but of his possessions right down to this fifteenth year of the emperor Severus there is no indication whatsoever?
So this establishes that an original manuscript was composed in 207 CE. This is where most discussions end in academia unfortunately. There is an unconscious desire to venerate the material which survives so as to provide us with 'accurate' information about the development of the early Church.
Too bad, so sad, my friends. This wish is absolutely untenable given what the manuscripts themselves tell us.
Just look at the very opening preamble of Against Marcion (which is almost always ignored by these people). You know, the one in which the author (or editor) acknowledges that we possess a third revision of that original manuscript:
Nothing I have previously written against Marcion is any longer my concern. I am embarking upon a new work to replace an old one. My first edition, too hurriedly produced, I afterwards withdrew, substituting a fuller treatment. This also, before enough copies had been made, was stolen from me by a person, at that time a Christian but afterwards an apostate, who chanced to have copied out some extracts very incorrectly, and shewed them to a group of people. Hence the need for correction. The opportunity provided by this revision has moved me to make some additions. Thus this written work, a third succeeding a second, and instead of third from now on the first, needs to begin by reporting the demise of the work it supersedes, so that no one may be perplexed if in one place or another he comes across varying forms of it. [Against Marcion 1.1]
Immediately following this preamble 'Marcion' is identified as coming from Pontus and familiar details follow.
It is impossible for us to know when this third rewrite was actually established. Yet if we imagine that the existing material was edited in the same general period - either by an aged Tertullian (see Jerome Lives) or a 'final editor' ad Nationes provides a much later date for this process to have occurred than is generally recognized. As Kaye notes:
In the first Address ad Nationes our author says, "in one place that 250 years, in another that 300 years had not yet elapsed since the birth of Christ" [Ecclesiastical History p. 40]
This can only mean that the final edition of at least one of the most important texts in the Tertullian corpus was established in its final form in the latter half of the third century. It seems then that the third rewrite of Against Marcion - where obvious signs of Montanism where edited out of the manuscript - must be placed in a similar date c. 250 - 275 CE.
