The KJV translates the same phrase “υπακοην πιστεως” as “obedience of faith” in Romans 16:26; so the KJV translators were capable of translating the phrase as such at Romans 1:5 if they wanted to. Yet at Romans 1:5 the KJV translators chose to translate the genitive construction “υπακοην πιστεως” as an objective genitive. "Obedience of faith" could be understood to mean "obedience to faith" just as the objective genitive phrase "right of life" could mean "right to life". The KJV interprets "πιστεως" as "the faith" (the specific Christian faith) in accordance with Strong's definition that "πιστις" can refer "by extension [to] the system of religious (Gospel) truth itself:" (Strong's Hebrew and Greek Dictionaries).
Some allege that the KJV translators were influenced by High Church theology and promoted obedience to a system of faith rather than the understanding that faith itself is obedience. However, the phrase “obedience to the faith” is not one that was artificially created by a biased translator. The phrase “obedient to the faith” appears in Acts 6:7 in even the ESV, NASB and NIV. Although the underlying Greek construction in Acts 6:7 is not the same as in Romans 1:5, the fact remains that the phrase "obedien[ce] to the faith" is biblical. In Acts 6:7, the phrase simply refers to priests becoming active believers in the Gospel faith. The context of Romans 1:5 supports the KJV rendering. Paul refers to his call of “apostleship,” which involves the responsibility of calling “all nations” (1:5) to obedience to the true faith of Jesus Christ. Thus, one might not agree with the way the KJV translators handled this flexible Greek construction, but the rendering in the KJV is acceptable in light of our understanding of other parts of scripture and Christian theology.
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