Rom 4:3: Gen 15:6 in the MT, the LXX, and Paul

Says Rom 4:3 quotes Gen 15:6: וְהֶאֱמִן בַּיהוָה וַיַּחְשְׁבֶהָ לּוֹ צְדָקָה (vehe'emin baYHWH vayyakhsheveha lo tsedaqah, "Abram believed the Lord, and it was credited to him as righteousness," BSB). וְהֶאֱמִן is waw with the Hiphil perfect, not the narrative wayyiqtol. וַיַּחְשְׁבֶהָ is a Qal wayyiqtol, 3ms, with a 3fs suffix ("he reckoned it"; BDB p. 362). צְדָקָה stands without a preposition.

Says Swete's LXX has καὶ ἐπίστευσεν Ἀβρὰμ τῷ θεῷ, καὶ ἐλογίσθη αὐτῷ εἰς δικαιοσύνην: a passive verb, Abram named, and εἰς before "righteousness." Paul has Ἐπίστευσεν δὲ Ἀβραὰμ τῷ θεῷ καὶ ἐλογίσθη αὐτῷ εἰς δικαιοσύνην, with δέ and the later name Abraham, repeating it at 4:9, 22–23.

Says The LXX makes the verb passive, ἐλογίσθη, and Paul keeps the passive (4:3, 9, 22); Paul himself names God as the one who credits (ὁ θεὸς λογίζεται, 4:6). In Romans the reckoning is God's.

Uncertain The subject and the suffix. The lean is that the Lord is the subject and "it" is Abram's believing, the feminine suffix standing for the act: Paul writes Ἐλογίσθη τῷ Ἀβραὰμ ἡ πίστις εἰς δικαιοσύνην (4:9), and Ps 106:31 uses the Niphal of the same verb for Phinehas (note.historical.Rom.3.1-Rom.3.31.works-of-the-law-4qmmt). The alternative makes Abram the subject, counting God's promise as righteousness.

How Paul develops the crediting (4:4–5) is treated in note.language.Rom.4.2-Rom.4.5.logizomai-misthos.

Gundry argues that Paul speaks of faith itself reckoned as righteousness, not of Christ's righteousness imputed; the Romans 4 exegetical notes treat that reading.

The root of וְהֶאֱמִן is treated at xref.Rom.1.17.Gen.15.6.heb.