ἀπιστέω

From the study of 2 Timothy 2:13

Range of meaning

Built from a- ('not') + the pist- family (trust, faith, faithfulness). It covers two connected senses: (1) to disbelieve, refuse to credit something or someone (Luke 24:11, 41; Mark 16:11, 16); (2) to be unfaithful, to fail in loyalty or prove untrustworthy (Rom 3:3). In Greek generally it also means 'to distrust' and, of people under obligation, 'to be disloyal'.

Against the English

KJV 'believe not' takes sense (1). Most modern versions ('are faithless', 'are unfaithful') take sense (2). YLT's 'not stedfast… stedfast' keeps the word-play best. 'Faithless' is accurate, but a modern reader can hear it as 'having no faith (in the sense of beliefs)', not 'breaking faith with someone'.

How it drifted

In English, 'faith' and 'faithful' have separated. 'Faith' usually means inner belief, and 'faithful' means loyal. Greek used one word family for both, so the mirror here (un-pistos / pistos) is between our loyalty and his, not between our beliefs and his.

Used elsewhere in the period

Rom 3:3 is the closest parallel: 'What if some were unfaithful (ēpistēsan)? Will their unfaithfulness (apistia) cancel the faithfulness (pistis) of God?' There it clearly means Israel's covenant disloyalty, not a doctrinal error. Standard lexicons (BDAG) group 2 Tim 2:13 with Rom 3:3 under 'be unfaithful'. The Pastorals also use apistos of the person who is not loyal (1 Tim 5:8; Titus 1:15).

From the study of Romans 3:3

Range of meaning

ἀπιστέω has two main senses: (1) to disbelieve, refuse to credit something as true (Luke 24:11, 41; Mark 16:11), and (2) to be unfaithful, to fail to keep faith, to prove untrustworthy. The second sense is well established in ordinary Greek, where ἄπιστος can describe a servant or partner who cannot be relied on. The noun ἀπιστία covers the same ground: "unbelief" (Mark 6:6; Romans 4:20; 11:20, 23) or "unfaithfulness, breach of trust." BDAG gives both senses for each word.

Against the English

KJV's "did not believe… unbelief" and BSB/WEB's "did not have faith… lack of faith" keep only the first sense, so the reader hears a failure to believe. NIV and ESV ("were unfaithful… faithlessness") and YLT ("faithless") keep the second, and with it the link to verse 2's "entrusted."

How it drifted

In modern English "unbelief" means intellectual doubt or not holding a religious belief. In Greek the πιστ- word family always carried the idea of trust in both directions: trusting someone, and being someone who can be trusted. English splits these into separate words (believe / be faithful / entrust), and Greek does not.

Used elsewhere in the period

2 Timothy 2:13 has the same pairing: εἰ ἀπιστοῦμεν, ἐκεῖνος πιστὸς μένει, "if we are faithless, he remains faithful." The "unfaithful" sense is clearly what's meant there. In the Septuagint (the Greek Old Testament), the πιστ- family regularly translates the Hebrew אמן (ʾmn) family, which means firmness, reliability and fidelity (ʾemunah, ʾemet).