In a post on the collective blog Thoughts on Antiquity, Chris Zeichmann refers to a radical proposal to the Ioudaios debate, made by Bruce Malina and John Pilch in their Social-Science Commentary on the Letters of Paul. Malina and Pilch think Paul used “Israelite” as an implicit antecedent in every use of Ἕλληνές and Ἰουδαῖοι, the former, then, referring to Israelites whose lives were “Hellenistic” and not “Judean."
This interpretation is particularly problematic in the passage in 1 Cor 1:18–31, particularly v. 23, cited by Zeichmann: ἡμείς δὲ κηρύσσομεν Χριστὸν ἐvσταυρωμένον, Ἰουδαίοις μὲν σκάνδαλον, ἔθνεσιν δὲ μωρίαν…, where Ἰουδαίοις is parallelled with ἔθνεσιν, i.e., Ἕλληνές is equivalent to ἔθνη. However, Malina and Pilch instead defend the variant reading consistent with their hypothesis, Ἕλλησι for ἔθνεσιν, which is found in "a number of good manuscripts" (Malina and Pilch, 67).
Zeichmann complains about the appeal to a number of good MSS on the part of Malina and Pilch, since the reading Ἕλλησι is supported mostly by later minuscules. (He cites minuscule 6 being the earliest, but at the same time he neglects to mention the important witness 1739). Among the majuscules, Zeichmann points out that the reading is attested only by later hands in C (04) and D (06); he does not note that it is also present in 049 and 056 (so Swanson). The reading is also attested in Clement of Alexandria, and seems to be earlier than Zeichmann thinks. Nevertheless, ἔθνεσιν has best manuscript support (Aleph, A, B, C*, D*, F, G, L, P, Psi, 33, 1836, alii). P46 is lacunose at this point.
As for internal criteria, Zeichmann rightly criticizes Malina and Pilch's suggestion that “[T]he coupling ‘Jews and Gentiles’ disturbs the parallelism of the next sentence speaking of ‘Jews and Greeks.’"(Malina & Pilch, 67) Zeichmann says, "To start, suggesting that parallelism was lost in transmission goes against almost every principle behind the practice of textual criticism. The scribal tendency to create parallelism and to harmonize passages – especially with roughly synonymous words – is as demonstrable a fact as one can find in current biblical studies."
I largely agree with Zeichmann when he sums up by saying that "if Paul believed ἔθνη and Ἕλλην to be totally synonymous – as a text-critically conscious reading of this text might suggest – , then such a reading [the interpretation of Malina and Pilch] becomes completely untenable."