See the Vatican version here:
6 qui reddet unicuique secundum opera eius:
7 his quidem, qui secundum patientiam boni operis gloriam et honorem et incorruptionem quaerunt, vitam aeternam;
8 his autem, qui ex contentione et non oboediunt veritati, oboediunt autem iniquitati, ira et indignatio.
It seems understandable that in verse 7 vitam aeternam is accusative because it acts like the object of reddet; but why is ira et indignatio not in the accusative?
Regarding why the Latin text uses the accusative and then the nominative, this is simply because the Vulgate is closely following the Greek original:
6 ὃς ἀποδώσει ἑκάστῳ κατὰ τὰ ἔργα αὐτοῦ·
7 τοῖς μὲν καθ’ ὑπομονὴν ἔργου ἀγαθοῦ δόξαν καὶ τιμὴν καὶ ἀφθαρσίαν ζητοῦσιν ζωὴν αἰώνιον·
8 τοῖς δὲ ἐξ ἐριθείας καὶ ἀπειθοῦσι τῇ ἀληθείᾳ πειθομένοις δὲ τῇ ἀδικίᾳ ὀργὴ καὶ θυμός,
9 θλῖψις καὶ στενοχωρία, ἐπὶ πᾶσαν ψυχὴν ἀνθρώπου τοῦ κατεργαζομένου τὸ κακόν, Ἰουδαίου τε πρῶτον καὶ Ἕλληνος
Most commentaries that call attention to this lack of parallelism suggest a simple elipsis, either of ἀποδοθήσονται (Latin: reddentur) or ἔσονται (Latin: erunt).
McFadden, in Judgment According to Works in Romans, pg. 44, n. 5, says:
Syntactically, only ζωὴν αἰώνιον (Rom. 2:7) supplies an accusative object for apodosei (2:6). But semantically, ὀργὴ καὶ θυμός (2:8) θλῖψις καὶ στενοχωρία (2:9), and δόξα δὲ καὶ τιμὴ καὶ εἰρήνη (2:10) also supply objects to ἀποδώσει (2:6). The objects are transposed into the nominative case and should be understood with an assumed future passive form of the verb ἀποδίδωμι [= ἀποδοθήσονται].
Robertson, in Word Pictures in the New Testament - Romans, comments on this verse:
...[T]he construction changes and the substantives that follow are not the object of ἀποδώσει like ζωὴν αἰώνιον above, but are in the nominative as if with ἔσονται (shall be) understood.
The nouns ira and indignatio are declined in the nominative because there is an implied verb ἔσται (Latin erit), i.e., “there shall be.” The same ellipsis occurs in Rom. 2:9 with the phrase «θλῖψις καὶ στενοχωρία» (Vul: tribulatio et angustia). As Heinrich August Wilhelm Meyer commented on Rom. 2:8,
Meyer, Heinrich August Wilhelm. Critical and Exegetical Handbook to the Epistle to the Romans. Trans. Moore, John C.; Johnson, Edwin. Ed. Dickson, William P. New York: Funk, 1884.
1 p. 87–88
