As Baumgarten rightly quotes, Lucian of Samosata in his famous Peregrinus depicts Jews and Christians as 'a cluster of bats coming out of a nest, or frogs holding council round a marsh, or worms assembling in some filthy corner' which he interprets in the light of Jonathan Z. Smith (‘What a difference a difference makes’, 47) as an expression of '... even identity' and calls the debate between Jews and Christians a 'Jewish discussions'. Hence, according to Lucian, Christians are seen as part of Judaism, not separated from Judaism (403), although Baumgarten shares the views of those Jews who see in these Christians anything, but Jews. That is the reason why he underlines against the apologetic trend of modern scholarship the difference between Christians and Jews, despite what he quoted from Lucian, relying on the Jew from Celsus. However, what this Jew complaints about, that Christianity was 'another name and another life' to which some Jews have 'deserted' is not very different from how Paul would have regarded those Jews whom he persecuted with all his powers. And even the 'mother-daughter' image of this Jew is not different from what we read in Tacitus (dismissed by Barclay, see below). It is obvious (and I don't know many amongst those criticized representatives of 'modern scholarship' that would deny that Celsus' Jew, like the persecuting Paul before him, held such views) that from a Jewish perspective, critical of the 'Christian' interpretation, 'Christians' were seen as deviators, perhaps even apostates of Judaism - which does not say much about how 'Christians' would have regarded themselves (as one can see, again with Paul who despite having joined the persecuted communities did not regard himself or his new brethren as apostates from Judaism). Baumgarten, then, supports his Jewish argument by pagan writers who, according to him, share this view that 'Christians' were no longer Jews (410), with reference to Barclay. He then takes on Lucian's P. again and mentions the 'new cult' and martyrdom (note this terminology reminds of Marcion's catchword 'new' and the fact that the Marcionites were known for having produced most martyrs in the second century) and mentions that for Lucian Christians are something else than Jews (no surprise from somebody who writes contemporary to Justin/Irenaeus and reports about somebody around the year 144 - note, it is the year in which Marcion went public with his New Testament). Galen, all agree, still sees Jews and Christians as 'one school' which is now one of two lawgivers (Moses and Christ; see also the notes of Celsus on the 'contradictory laws' CC 7.18; 'Moses or Jesus', 'opposite purpose' which supports the case I have made in my Marcion and the Synoptic Gospels [Leuven, 2014], that the Jewish source of Celsus was aquainted with and critical of Marcion’s Antitheses). When Baumgarten draws the conclusion, based on his retake of Lucian (no longer mentioning what he quoted from him earlier - the cluster of bats coming out 'from a nest', not nests), and against Galen (but supported by what he found by Barclay, see below), he comes to the conclusion: ‘The nearly unanimous evidence of the “pagan” authors, taken together with the explicit remarks of Celsus’ Jew, make it hard to argue that, “Most, if not all of the Christians of the first, second, and perhaps even the third centuries considered themselves and were considered by others as Jews” or that the elites on what would become the two sides (to whom Celsus’ Jew would have belonged) were so concerned with distinguishing between Jews from Christians because so many other people of Antiquity did not see the difference between Jews and Christians, that is, because the ways had not yet really parted’ (412-3). As Baumgarten himself italizes the passage in Boyarin’s quote (Daniel Boyarin, ‘Semantic Differences’, in Adam H. Becker, Annette Yoshiko Reed (eds), The Ways that Never Parted [Tübingen, 2003], 65-86, 69), his concern has not been about how Christians saw themselves, but how they were seen by others.
As he has based the core of his argument on Barclay’s article, we also need to review the latter. Here my observations:
In his contribution on ‘“Jews” and “Christians” in the Eyes of Roman Authors c.100 CE’, John M.G. Barclay suggests that ‘as far as Romans were concerned, the association between “Christians” and “Jews” was not an early, but a late phenomenon; two groups once clearly differentiated could now be closely associated, but only when a good deal was discovered about “Christian” beliefs and the “Christian” self-image. It was only late, and then only patchily (and in elite circles) that Romans began to identify “Christians” with “Jews”, an association certainly not made by 100CE’ (326).
This hypothesis is based on the assessment of a relatively coherent picture that Barclay sees being painted by Roman authors of the first and early second century who write about ‘Jews’ (Valerius Maximus, Apion of Alexandria, Seneca, Petronius, Pliny the Elder, Quintilian, Martial and Juvenal), about ‘Jews’ and ‘Christians’ (Suetonius and Tacitus), a picture that he contrasts with the profile of ‘Christians’ given by those authors who talked about ‘Jews’ and ‘Christians’, and those who talked about ‘Christians’ alone (Pliny the Younger, Trajan) or on ‘Galileans’ (Epictetus).
While ‘Jews’ are seen as a superstitious gens, ‘Christians’ are regarded as criminals, two ‘different’ categories, therefore, as Barclay suggests who never before Celsus have been connected.
In order to maintain this neatly differentiated picture, he needs to exclude the Claudian edict (taken as an individual rebel ‘not a representative of a group’ , although according to the edict the Emperor ‘expellat Iudaeos’. Would an Emperor issue an edict, if the rebellious Chrestos were only a single phenomenon with the Jewish synagogue without impact on a group? That the Emperor expells ‘Jews’ contradicts Barclay’s reading – the Emperor does not exclude and expell an individual rebel, but ‘Jews’, amongst them the famous Aquila).
The second witness which Barclay needs to exclude (317) to make his case is Tacitus’ lost work, the Historiae, where Tacitus reports about Titus who wanted to destroy
completely the religion of the Jews and the Christiani: For although these religions are conflicting, they nevertheless developed from the same origins. The Christiani arose from the Jews: With the root removed, the branch is easily killed.
Only recently E. Laupot (not mentioned by Barclay) has made a good case that the text is genuinely by Tacitus. The quote is, indeed, of interest as it gives, if not the opinion of Titus, at least that of Tacitus that for him, Jews and Christians still belonged to one religion, while at the same time he can also speak of them as two religions with a clear indication that the Christians derive from the Jews and can be seen like branch and root.
The third evidence that Barclay dismisses is Epictetus. When Epictetus talks about a Jew who ‘has been baptised and has made his choice’ and ‘is in reality a Jew’, Barclay takes this as evidence for proselyte baptism which, according to Barclay, ‘has nothing to do with Christian practice’ (319). Yet, for a long time, the terminology of ‘baptism’ has made scholars think that there was a potential connection to Christians (see, for example, James D.G. Dunn, Beginning from Jerusalem (Cambridge, 2009), 55-6 (not mentioned by Barclay).
In addition, one does not only need to look at the positive evidence, but also at the negative one. If the two groups were as differentiated and distinct from early on, as Barclay claims, one needs to explain why, for example, Josephus who talks about the different groups of Judaism and also mentions key figures like James, Jesus’ brother, never speaks of ‘Christians’. Likewise, James D.G. Dunn is more precise when he states that ‘there are no references to Christians or Christianity in non-Christian Greco-Roman sources prior to the second century’ (54), but that all we have are second century authors writing about first century events. This reduces the basis for the claim that from early on, we have a differentiation between Judaism and Christianity which only towards the later second century were brought together by authors.
A more systematic problem is given by the fact that Barclay states that ‘Jews’ and ‘Christians’ are incomparable labels, belonging to a ‘different category’, yet – in his contrasting of two groups, ‘Jews’ and ‘Christians’ he starts blurring the difference between a label (which can be distinct, as they are in the case of 'Jews' and 'Christians') and 'groups'. If the labels refer to distinct categories ('Jews' a gens, 'Christians' criminals), a comparison of 'Jews' with 'Christians' is like that of apples with pears, hence, such comparison will not give us an insight into how people were related to each other (let alone in their own minds), but will give us labels under which people have been categorised from different perspectives. Instead, if one followed Barclay's logic, one would need to say that if 'Jews' and 'Christians' are incomparable, Jews could easily also be seen as criminals (Christians) (without the need of people by making such strictures to refer to these people being Jews), as well as Christians could be seen as belonging to the gens of Jews (without in thise case people being in need in accusing them of being ‘Christians’ or criminals, as being a Jew was far from being a criminal). If 'Christians' as a label is equated with being a 'criminal' - and this is how I see it too, this label explains why the title ‘Christians’ has not become a self-reference for a long time and that writings like 2Peter and Acts still know of it as a shame name, and that even Justin has difficulties to give it a positive rendering. If this is so, how can such a shame name which has no reference to a gens give us any indication about the relation between 'Christians' and 'Jews' in the first half of the second, let alone about the first century?
 Tac., in: Sulp. Sev.: ‘Plenius Iudaeorum et Christianorum religio tolleretur: quippe has religiones, licet contrarias sibi, isdem tamen ab auctoribus profectas; Christianos ex Iudaeis extitisse: radice sublata stirpem facile perituram’.
 E. Laupot, ‘Tacitus' Fragment 2: The Anti-Roman Movement of the Christiani and the Nazoreans’, VigChr 54 (2000), 233-47.