G0570–ἀπιστία–apistia

And He performed but few mighty deeds there because of their want of faith.

ἀπιστίαν apistian “unbelief”

He wondered at their unbelief. So He went round the adjacent villages, teaching.

ἀπιστίαν apistian “unbelief”

Immediately the father cried out, "I do believe: strengthen my weak faith."

ἀπιστίᾳ. apistia “unbelief!”

Later still He showed Himself to the Eleven themselves whilst they were at table, and He upbraided them with their unbelief and obstinacy in not having believed those who had seen Him alive.

ἀπιστίαν apistian “unbelief”

For what if some Jews have proved unfaithful? Shall their faithlessness render God's faithfulness worthless?

ἀπιστία apistia “unbelief”

Nor did he in unbelief stagger at God's promise, but became mighty in faith, giving glory to God,

ἀπιστίᾳ, apistia “through unbelief,”

This is true; yet it was their unbelief that cut them off, and you only stand through your faith.

ἀπιστίᾳ apistia “unbelief”

Moreover, if they turn from their unbelief, they too will be grafted in. For God is powerful enough to graft them in again;

ἀπιστίᾳ, apistia “in unbelief,”

though I was previously a blasphemer and a persecutor and had been insolent in outrage. Yet mercy was shown me, because I had acted ignorantly, not having as yet believed;

ἀπιστίᾳ· apistia “unbelief;”

see to it, brethren, that there is never in any one of you--as perhaps there may be--a sinful and unbelieving heart, manifesting itself in revolt from the ever-living God.

ἀπιστίας apistias “of unbelief”

And so we see that it was owing to lack of faith that they could not be admitted.

ἀπιστίαν. apistian “unbelief.”