Julian the Apostate (r. as Augustus 360-3) as an emperor attempted to take the Roman empire back from Christianity and return it to a neo-platonist form of paganism (for those who wish to read more about him, this is an encyclopedia article written by two academics which describes his career). He did this both in his policies as emperor- and also in publications. Julian thought of himself as a philosopher and mystic- a devotee of Hellenic values in the world usurped by the Galileans (as he called Christians). The focus of his arguments is what interests me here: in a fascinating article for the Journal of Late Antique Religion and Culture, Gorgio Scrofani has attacked an issue which might seem perplexing. Julian's major treatise 'Against the Galileans' includes a paean of praise to Judaism- what Scrofani does is explicate where this defence of the Jews fits into Julian's attack on Christianity and his defence of paganism.
As a defender of Judaism, what Julian sought to do was to defend Jewish ritual and tradition. He wrote
Jews agree with the Gentiles, except that they believe in only one God. That is indeed peculiar to them and strange to us; since all the rest we have in a manner in common with them, temples, sanctuaries, altars, purifications and certain precepts. For as to these we differ from one another not at all or in trivial matters.
This passage is interesting- carefully read it demonstrates that Julian established in his reader's mind that the distinction between monotheism and polytheism was less important than the distinction between a religion of ritual and one that disdained those rituals. What Scrofani argues is that Julian's point here was an attempt to do two things. Firstly it was an attempt to show that Christianity was an innovation of inpurity: Christians, Julian commented at other points, needed to be purified before they could take part in pagan rites. Julian was preoccupied by purity- he wanted priests who were morally and physically pure- because he saw in the maintenance of ritual, the way towards the maintenance of imperial Rome. He saw purity as a guarentee of the stability of the state in the eyes of the gods and therefore of men.
This was also though an attack on an area of vulnerability in the faith. What Julian did by using the Jewish example was attempt to open a breach in the Christian world. His attempt was to take the fight, as it were, to the territory of the Christians, to the old and new Testaments. This attempt to divide the Jews from the Christians picked up on anxieties within the new faith- we know from John Chrysotom and others that there were many Christians who even as late as the third and fourth centuries kept rituals like the day of atonement going. By splitting religion on the basis of ritual- Julian's argument drew together the Hellenes and Jews as heirs of the religious innovations of Chaldea against the Christians.
What's interesting about Scrofani's article is that the nature of Julian's attack and the nature of the breach that he hoped to widen should tell us something about what was new and astonishing in Christian doctrine. Those who argued against Christianity at its inception can tell us a lot about what the new religion was and what was astonishing about it. They also inform us about the preoccupations of the time. For Julian what was new and controversial about Christianity was its failure to emphasize ritual and cultic purity: he saw this as a moral failing- and suggested that it marked a boundary between Judaism and paganism on one side and Christianity on the other. He also saw this as an opportunity- because so many of his contemporaries shared his anxiety. These words from the last pagan Emperor therefore tell us a lot, as Scrofani argues, about the context in which early Christianity developed and about the thing that developed in that context.