'Unbelieving' in the Bible

And Jesus answered [and] said, "O unbelieving and perverse generation! {How long} will I be with you? {How long} must I put up with you? Bring him here to me!"

And he answered them [and] said, "O unbelieving generation! {How long} will I be with you? {How long} must I put up with you? Bring him to me!"

So Jesus answered [and] said, "O unbelieving and perverted generation! {How long} will I be with you and put up with you? Bring your son here!"

Then he said to Thomas, "Place your finger here and see my hands, and place your hand and put [it] into my side. And do not be unbelieving, but believing!"

Now to the rest I say--not the Lord--if any brother has an unbelieving wife and she consents to live with him, he must not divorce her.

And if any wife has an unbelieving husband and he consents to live with her, she must not divorce her husband.

For the unbelieving husband is sanctified by his wife, and the unbelieving wife is sanctified by the brother, since otherwise your children are unclean, but now they are holy.

To the pure all [things] [are] pure, but to those who are defiled and unbelieving nothing [is] pure, but both their mind and conscience are defiled.

Watch out, brothers, lest there be in some of you an evil, unbelieving heart, [with the result that you] fall away from the living God.