We had an interesting seminar here in Cambridge on Tuesday with Chris Tuckett (Oxford) on Nomina Sacra. Basically the first half was a summary of his argument (against Roberts and Hurtado) in C. M. Tuckett, ‘“Nomina Sacra”: Yes and No?’, in J.-M. Auwers & H. J. de Jonge (eds), The Biblical Canons (Leuven, 2003), 431-458. In discussion it turned out that Tuckett agrees that by the 3rd/4th century nomina sacra did function in a 'religious' manner (i.e. it reflects a religious attitude to the names) [evidence for this esp in the emergence of SWTHR as a nomen sacrum in this period; also 1 Cor 8.5 in P46; purple gospels etc.]; but he doesn't buy this theory for the origin of the nomina sacra (which is what Roberts and Hurtado argued). He proposes that they originated as reading aids for Christians unused to uncial texts.
Essentially Tuckett gathers up everything that Roberts dismissed as minor exceptions to the main rule (and finds a few more) and says 'aha' there are enough exceptions here to prove that the supposed rule is wrongly conceived. The second half of the seminar looked at some very unusual uses of nomina sacra in E 08 (Laudianus).
My own reflections, for what they are worth, are as follows:
1. Once Tuckett has admitted that the NS did function as 'sacred names' for scribes in a later period (i.e. sixth century purple gospels; the 3-4th century emergence of SWTHR; the early 3rd cent P46), then he has to explain the emergence of a religious dimension as somewhat in discontinuity with the point of origin. But there is no evidence that would point to discontinuity and the selection of words for abbreviation do look 'religious' (as also in Ep Barn 9 & Test Sol 11).
2. Since the problem about the 'origin' of the NS is related precisely to our lack of evidence from the earliest period why don't we say that we are not sure about the point of origin of the practice, but that it appears to function in 'religious' way in most of the manuscripts.
3. Once we are onto manuscripts we'll gain more by careful analysis of the individual practices of the scribes, something that we don't really have for all the major early biblical manuscripts. More research needs to be done here.