I am in a bit of a rush today because I have to give an 'important' presentation today. Nevertheless I think I find that my writing is less convoluted when I am pressed for time, so I am hopeful that I will display some additional clarity today when I am pressed for time. Let's start from the beginning. The syntagma at the heart of second century Christianity defined the religion forever more. At its core, this syntagma was an 'arrangement' of dangerous or bad things which should be avoided in order to manifest 'right thinking' (= orthodoxy).
Only a hundred or so people in the history of the world have bothered to think and publish their thoughts on this Christian syntagma tradition. Yet it is clearly the beginnings of the 'constitution' (a term we shall take literally for the moment) of the religion we have come to take for granted. In other words, what was termed 'Christianity' in the early second century was only defined when the terms 'Christian' and 'Christianity' - themselves clear Latinisms in the Greek language - were being introduced.
In other words, this was a 'bang, bang' proposition. As soon as the terms 'Judaism' and 'Christianity' were coined, the defined the Biblical religions along the lines of 'messiah to come' and 'messiah already came' among other definitions. Things were not as clear before the Hadrianic period when no such terms as 'Judaism' and 'Christianity' existed. There were many groups which had clear overlap - i.e. that were in some sense 'Jewish' or 'Samaritan' and what we would call 'Christian' even though the later term had not yet been invented.
The point here is that most scholarship simply assumes the existence of this 'Christian identity' dating back to the 'apostolic era' in the first century. This is simply untenable given the ignored importance of the second century syntagma. As we saw from Eusebius's discussion in Church History, the anti-Marcionite syntagma referenced in the fourth book of Against Heresies associated with Justin and the syntagma Justin says was 'against all heresies' is one and the same. This seems to be confirmed by our assumption that Celsus used the same syntagma as referenced in statements cited at the end of Origen's fifth book where Origen cryptically alludes to Celsus's knowledge of "the existence of certain Simonians who worship Helene, or Helenus, as their teacher, and are called Helenians," "certain Marcellians, so called from Marcellina, and Harpocratians from Salome, and others who derive their name from Mariamme, and others again from Martha ... [and']the Marcionites, whose leader was Marcion."
What has been ignored hitherto I think is that Celsus's references consistently take the form of various 'voluntary associations' which Origen fills in the blanks for the reader. In other words, Celsus merely says 'Simonians' and Origen goes on to explain the association with Simon - "it has escaped the notice of Celsus that the Simonians do not at all acknowledge Jesus to be the Son of God, but term Simon the "power" of God, regarding whom they relate certain marvellous stories, saying that he imagined that if he could become possessed of similar powers to those with which be believed Jesus to be endowed, he too would become as powerful among men as Jesus was amongst the multitude." [Against Celsus 5.62]
If the reader looks carefully at the entire section it is clear that Celsus is citing from something he doesn't fully understand (very common in the annals of 'heresiology'). He has an early and now lost syntagma with a list of prohibited 'voluntary associations' one of which is clearly the group identified by Origen as the Μαρκιωνιστῶν, προϊσταμένων
Μαρκίωνα. It is important to note that Justin's syntagma is identified by Irenaeus as τῷ πρὸς Μαρκίωνα συντάγματί. Clearly Marcion is identified by both third century Church Fathers as the name of the heretic who founded the group of Marcionites. The question is of course whether the original treatise was against a man named Marcion or a voluntary association called the followers of Mark (= Μαρκίων).
If we allow for this possibility we finally explain (a) why Origen took such an interest defending 'Christianity' from Celsus's assault and (b) why Marcion is never named in the text. Origen was an Alexandrian with a personal (and possibly 'secret') attachment to Mark. The invention of 'Marcion' the heretic was developed to allow a rehabilitated 'Mark' (the disciple of Peter) to return to the Christian fold. In other words, Celsus's syntagma only mentioned the Μαρκίων a quasi Jewish voluntary association akin to other known Jewish synagogal groups - i.e. the Agrippesians (Ἀγριππησίων) and the Augustesians (Αὐγυστησίων). It was only with the development of the myth associating an adapted 'Catholic' form of this original syntagma for use in the churches in the late second century which introduced the person of 'Marcion.'
Stephan Huller has had a life long interest in religion and spirituality 
dating back to conversations with his grandfather, Gaston Frank. "He said we represent one of the last descendants of the Frankist Jewish faith in the world," he muses. "I grew up thinking that our family was something like the Last of the Mohicans."