νόμος with and without the article (2:12–27)

Says In SBLGNT, νόμος (nomos) occurs 19 times in 2:12–27: 12 times without the article and 7 times with it. The two forms alternate within single sentences: ἐν νόμῳ … τοῦ νόμου (2:23); τὸν νόμον … παραβάτην νόμου (2:27). In 2:17–20 νόμῳ, ἐκ τοῦ νόμου and ἐν τῷ νόμῳ all name the law the Jew relies on.

Implies In this passage the article does not switch between "law in general" and the law of Moses. Anarthrous nouns after prepositions (ἐν νόμῳ, διὰ νόμου) and as the genitive of an anarthrous head (ἀκροαταὶ νόμου, παραβάτης νόμου) are normal Greek. In 2:17–27 the anarthrous forms clearly mean the law the Jew has, teaches and breaks. The Byzantine τοῦ νόμου (2:13) and τῷ νόμῳ (2:17) add the article without changing the referent (var.Rom.2.13.tou-nomou; var.Rom.2.17.to-nomo).

Abbott-Smith classes anarthrous νόμος at Rom 2:12 and 2:14b as "of law in general" and 2:14a as the Mosaic law "in its quality as law."

Uncertain Whether the anarthrous νόμος of 2:12–14 is the Mosaic law or law as such (Abbott-Smith's view for 2:12, 14b, and the main alternative). This note leans to the Mosaic law: the Gentiles of 2:14 "do not have" it, which fits a specific, possessed law, and 2:12 contrasts sinning ἀνόμως with sinning ἐν νόμῳ. The clearest qualitative use is the predicate ἑαυτοῖς εἰσιν νόμος, "they are a law to themselves" (2:14).