Commentaries:
Robertson's Word Pictures (NT)
For what if? (ti gar ei). But Westcott and Hort print it, Ti gar ei. See Philippians 1:18 for this exclamatory use of ti gar (for how? How stands the case?).
Some were without faith (hpisthsan). First aorist active indicative of apistew, old verb, to disbelieve. This is the common N.T. meaning (Luke 24:11, Luke 24:41; Acts 28:24; Romans 4:20). Some of them "disbelieved," these "depositaries and guardians of revelation" (Denney). But the word also means to be unfaithful to one's trust and Lightfoot argues for that idea here and in II Timothy 2:13. The Revised Version renders it "faithless" there. Either makes sense here and both ideas are true of some of the Jews, especially concerning the Messianic promises and Jesus.
The faithfulness of God (thn pistin tou qeou). Undoubtedly pistiv has this sense here and not "faith." God has been faithful (II Timothy 2:13) whether the Jews (some of them) were simply disbelievers or untrue to their trust. Paul can use the words in two senses in verse Romans 3:3, but there is no real objection to taking hpisthsan, apistian, pistin, all to refer to faithfulness rather than just faith.
Other Robertson's Word Pictures (NT) entries containing Romans 3:3:
Romans 3:3
Romans 10:16
2 Thessalonians 3:3
2 Timothy 2:11
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