Verses for of unbelief

Take heed, brethren, lest there be in any of you an evil heart of unbelief, in departing from the living God.

So we see that they could not enter in because of unbelief.

Seeing therefore it remaineth that some must enter therein, and they to whom it was first preached entered not in because of unbelief:

Let us labour therefore to enter into that rest, lest any man fall after the same example of unbelief.

Well; because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear: