'Unbeliever' in the Bible

If he pays no attention to them, tell the church. But if he doesn’t pay attention even to the church, let him be like an unbeliever and a tax collector to you.

Then He said to Thomas, “Put your finger here and observe My hands. Reach out your hand and put it into My side. Don’t be an unbeliever, but a believer.”

But if the unbeliever leaves, let him leave. A brother or a sister is not bound in such cases. God has called you to live in peace.

But if all are prophesying and some unbeliever or uninformed person comes in, he is convicted by all and is judged by all.

What agreement does Christ have with Belial? Or what does a believer have in common with an unbeliever?

But if anyone does not provide for his own, that is his own household, he has denied the faith and is worse than an unbeliever.