Harnack sees a continuum between Epiphanius and Tertullian and Irenaeus's promised Against Marcion:
Epiphanius Beitrag zu unserer Kenntnis des Apostolikon M.s ist night umfangreich: geraume Zeit bevor er has Kapitel (42) seines Panarions gegen M ausgearbeitet, hatte er einmal (wo? in Cypern? in Palestina?) jenes Apostolikon samt dem zugehorigen Evangelium in de Hande bekommen und aus diesem 78, aus jenem 40 Stellen ausgescrieben, um den Ketzer aus seinem Werken selbst zu widerlegen, was vor ihm schon Irenaeus geplant und Tert ausgefuhrt hatte.
I see it as more straightforward that both men had access and used this lost work. But here's what I find interesting. Tertullian says that his text is the third of three rewritten treatises called Against Marcion:
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 brother, 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.
Si quid retro gestum est nobis adversus Marcionem, iam hinc viderit. Novam rem aggredimur ex vetere. Primum opusculum quasi properatum pleniore postea compositione rescideram. Hanc quoque nondum exemplariis suffectam fraude tunc fratris, dehinc apostatati, amisi, qui forte descripserat quaedam mendosissime et exhibuit frequentiae. [2] Emendationis necessitas facta est. Innovationis eius occasio aliquid adicere persuasit. Ita stilus iste nunc de secundo tertius et de tertio iam hinc primus hunc opusculi sui exitum necessario praefatur, ne quem varietas eius in disperso reperta confundat.
Interestingly Epiphanius says in very similar language that his is the second of two texts written this way:
Παραθήσομαι δὲ καὶ ἣν ἐποιησάμην κατ' αὐτοῦ πραγματείαν πρὶν τοῦ ταύτην μου τὴν σύνταξιν ἐσπουδακέναι διὰ τῆς ὑμῶν τῶν ἀδελφῶν προτροπῆς ποιήσασθαι.
I am also going to append the treatise which I had written against him before, a your instance, brothers, hastening to compose this one.
ἀπὸ ἐτῶν ἱκανῶν, ἀνερευνῶν τὴν τούτου τοῦ Μαρκίωνος ἐπινενοημένην ψευδηγορίαν καὶ ληρώδη διδασκαλίαν, αὐτὰς δὴ τὰς τοῦ προειρημένου βίβλους ἃς † κέκτηται μετὰ χεῖρας λαβών, τό τε παρ' αὐτῷ λεγόμενον εὐαγγέλιον καὶ τὸ ἀποστολικὸν καλούμενον παρ' αὐτῷ ἐξανθισάμενος καὶ ἀναλεξάμενος καθ' εἱρμὸν ἀπὸ τῶν προειρημένων δύο βιβλίων τὰ ἐλέγξαι αὐτὸν δυνάμενα, ἐδάφιόν τι συντάξεως ἐποιησάμην, ἀκολούθως τάξας κεφάλαια καὶ ἐπιγράψας ἑκάστῃ ῥήσει ˉα ˉβ ˉγ.
Some years ago, to find what falsehood this Marcion had invented and what his silly teaching was, I took up his very books which he had < mutilated >, his so-called Gospel and Apostolic Canon. From these two books I made a series of < extracts > and selections of the material which would serve to refute him, and I wrote a sort of outline for a treatise, arranging the points in order, and numbering each saying one, two, three (and so on). And in this way I went through all of the passages in which it is apparent that, foolishly, he still retains against himself these leftover sayings of
the Savior and the apostle.
I wonder whether Epiphanius's statement "I am also going to append the treatise which I had written against him before, a your instance, brothers, hastening to compose this one" is based on something originally in Irenaeus and twisted by Tertullian into
