21 But to Israel he says:
“All day long I have stretched out My hands
To a disobedient and contrary people.”
in Rom 10:21 the word that is translated “disobedient” is actually ἀπειθέω (G544) – apeitheo, or “unpersuadable”, or “one who won’t allow self to be persuaded”, “one refusing or withholding belief”, etc. This adjective comes from the verb πείθω (G3922) – peitho – to be persuaded. The noun “πίστις” (G4102) – pistis – “faith” – is actually derived from the latter verb.
ἀπειθέω in Romans 10:21 is translated “disobedient”, which is fine, as long as we understand that it’s talking about a refusal to believe / trust / rely on what God has provided by grace. A better translation would be “unbelieving”, or “unpersuadable”. The same translation peculiarity for the same word bears out in a number of other places in NT, e.g.:
“Since therefore it remains that some must enter it [the rest], and those to whom it was first preached did not enter because of disobedience [unpersuadableness / unbelief]”
This uncovers a very important point: “disobedience”, or acting amiss, originates from a place of not trusting God. It all starts in the heart. Specific acts follow from that.