Signs that Against Marcion was Written During the Reign of Commodus

[Secret Alias]

And another problem. If Against Marcion goes back to something written by Justin and Justin doesn't know Paul and the Marcionites were a Pauline sect ... well, you see where a need for a rewrite was predicated

[Secret Alias]

Or if you take the possibility that Justin knew who Paul was but didn't mention him because he was secret or sacred to Justin then the beginning of Book 5 (where the third author questions the "secret Paul" of the Marcionites and the anonymous gospel i.e. no identification of authorship) takes on additional significance

[Secret Alias]

What was the thesis of the original book?

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Answer: something about "the Antitheses." Not a satisfactory answer but really that's all we know for certain