Hab 2:4b behind Rom 1:17: בֶּאֱמוּנָתוֹ

Says Rom 1:17 quotes Hab 2:4b, which in the MT reads וְצַדִּיק בֶּאֱמוּנָתוֹ יִחְיֶה (vetsaddiq be'emunato yikhyeh, "but the righteous one by his faithfulness will live"). בֶּאֱמוּנָתוֹ is the preposition be- ("by, in"), the feminine noun אֱמוּנָה (emunah) in construct, and the 3ms suffix -o ("his"); OSHB tags it HR/Ncfsc/Sp3ms. יִחְיֶה is Qal imperfect 3ms, "he will live."

Says The accents join the phrase to the verb: וְצַדִּ֖יק בֶּאֱמוּנָת֥וֹ יִחְיֶה has a disjunctive tifcha on וְצַדִּיק and a conjunctive merkha on בֶּאֱמוּנָתוֹ. The Masoretes read "the righteous one, by his faithfulness he will live."

Says The noun belongs to the root of וְהֶאֱמִן (vehe'emin, "and he believed," Hiphil, Gen 15:6). BDB (p. 53) glosses it "firmness, steadfastness, fidelity," with the senses "firmness, steadiness," "steadfastness," and "faithfulness, trust." The concrete use is Exod 17:12, where Moses' hands were אֱמוּנָה, "steady" (BSB). The noun usually names reliability, in God or in people, rather than the act of believing.

Implies In Hab 2:4 the righteous person's אֱמוּנָה is steady, loyal reliance on God while the vision waits (2:3), in contrast with the proud one whose soul "is not upright" (2:4a). Here keeping faith and trusting God's word are one posture, so Greek πίστις, which covers both "faith" and "faithfulness," is a fair rendering.

Uncertain Whether English should say "faith" (BSB) or "faithfulness." The team reads it as trusting faithfulness: faith that endures.